Scientific Calculator fx-991 Downloads & RevenueScientific Calculator fx-991 · App Store & Google Play
Scientific Calculator fx-991 gets 1k+ downloads a day worldwide (AppInsider estimate, November 2026, rounded down to a band).
Scientific Calculator fx-991 by Dinh Phuc is on App Store and Google Play. Active Users (MAU & DAU), Downloads, rankings, keywords, revenue, and rating totals.
Scientific Calculator fx-991 update history & changes
Last change · 19 events since 15 Oct 2019Full timeline ↓📊iOSPassed 100k monthly users📦iOSUpdated to version 1.9.3📈iOSCharting in a new country🔎iOSTop 10 for “calculator”🔎iOSTop 10 for “calculator”📈iOSCharting in a new country🆕AndroidFirst spotted by AppInsider🆕iOSFirst spotted by AppInsider📦iOSVersion 1.9.2📦AndroidVersion 1.8.6🆕iOSReleased on the App Store🆕AndroidReleased on Google Play
Full timeline · 19 events
- 📊Scientific Calculator fx-991 passed 100k monthly usersiOSour estimate
- 📦Scientific Calculator fx-991 updated to version 1.9.3iOS- Added Daily Challenge with 10 new math questions every day.
- Track your personal progress and compete on the 7-day leaderboard. - 📈Scientific Calculator fx-991 charting in a new countryiOSItaly
- 🔎Scientific Calculator fx-991 reached Top 10 for “calculator”iOS#8 in Sweden search · popularity 75
- 🔎Scientific Calculator fx-991 reached Top 10 for “calculator”iOS#9 in Poland search · popularity 74
- 🔎Scientific Calculator fx-991 reached Top 10 for “calculator”iOS#2 in South Korea search · popularity 73
- 📈Scientific Calculator fx-991 charting in a new countryiOSAustralia
- 🆕Scientific Calculator fx-991 first spotted by AppInsiderAndroidVietnam
- 🔎Scientific Calculator fx-991 reached Top 10 for “calculator”iOS#9 in Turkey search · popularity 75
- 📈Scientific Calculator fx-991 charting in a new countryiOSSouth Korea
- 📈Scientific Calculator fx-991 charting in a new countryiOSUnited Kingdom
- 📈Scientific Calculator fx-991 entered the top 100iOSTop Free · Education · SA
- 📈Scientific Calculator fx-991 charting in a new countryiOSSaudi Arabia
- 📈Scientific Calculator fx-991 charting in a new countryiOSIndonesia
- 🆕Scientific Calculator fx-991 first spotted by AppInsideriOS#81 in Top Free · Education · India
- 📦Scientific Calculator fx-991 version 1.9.2iOS* Added one-variable polynomial division with quotient and remainder results.
* Improved the formula reference interface.
* Added the periodic table of chemical elements.
* Added the ability to save and manage favorite formulas.
* Improved performance and fixed minor bugs.… more - 📦Scientific Calculator fx-991 version 1.8.6Android✨ Updated the formula interface and added the Periodic Table.
❤️ Added favorite formulas and recently viewed formulas.
⚡ Improved calculation history for faster viewing and access. - 🆕Scientific Calculator fx-991 released on the App StoreiOS
- 🆕Scientific Calculator fx-991 released on Google PlayAndroid
Collected from the stores by AppInsider since we first spotted the app. Dates are when we saw each change.
Rating
4.7 ★
19k ratings, both stores
Measured
Best rank now
#35
App Store · 
Education Free
Education FreeMeasured
New ratings a week
9.9
▼ -11% vs the 2 weeks before
Measured
App Store
App details
App ID
1673640297
Publisher
Dinh Phuc
Publisher country
Vietnam
On the store since
Feb 2023
3 years on the store
Minimum OS
iOS 15.0+
iPhone 6s and later
Devices
iPhone · iPad
Universal purchase
Content rating
4+
Languages
59
AF SQ AR HY AZ EU BE BG CA HR CS DA …
Size
28 MB
Google Play
App details
App ID
com.hiedu.calculator580
Publisher
DO DANG HUY
Publisher country
Vietnam
Content rating
Everyone
Scientific Calculator fx-991 downloads & installs
Both stores, worldwide. Bands are open; exact numbers are free with an account.
| Store | Downloads / day | Lifetime installs |
|---|---|---|
| App Store | 100+ | 100k+ |
| Google Play | 1k+ | 1M+ Measured |
| Total | 1k+ Confidence | 1M+ Confidence |
How this is calculated
App Store: chart positions and rating growth per country, anchored on its own Android downloads; lifetime from ratings worldwide × installs per rating. Google Play: the daily change in its exact install count. The total adds every store.
Where Scientific Calculator fx-991's downloads come from Modelled
Last 30 days: organic search, browsing the store, features and paid ads.
Active users
All platforms, worldwide. Free with an account.
Stickiness (DAU / MAU)
how many monthly users open it on a given day
Retention · share of new users still active
Day 1
Day 7
Day 30
Time spent · per daily user
Average time spent Pro
min a day
Sessions a day Pro
Time per session Pro
min
How this is calculated
Monthly users come from lifetime installs across every store, fitted on monthly active user figures companies publish; daily users = monthly × the typical daily/monthly ratio for the category. Confidence is the chance the real number is within half to double ours.
In-app revenue
Worldwide, what users spend before Apple and Google take their fee.
| Store | Per day | Per month | Share |
|---|---|---|---|
| App Store | |||
| Google Play | |||
| Total | Confidence | 100% |
Business model: Subscription-led
How Scientific Calculator fx-991 makes money: subscriptions, one-off purchases and ads.
SubscriptionsIn-app purchasesAds · 1 ad networks
Subscriptions
/mo
of revenue
Ads
/mo
of revenue
Top in-app purchases · App Store US, most popular first
| 1 | Monthly Premium Access subscription | |
| 2 | HiEdu Pro Lifetime subscription | |
| 3 | Yearly Premium Access subscription | |
| 4 | Remove Ads 30 Days | |
| 5 | 6-Month Premium Membership subscription |
Where it ranks now
Both stores, across every country we track.
| Store | Best rank | Charting in | US Top Free | US Top Grossing |
|---|---|---|---|---|
| App Store | #35 Education Free | 2 of 30 countries | – | – |
| Google Play | #67 Education Free | 1 of 23 countries | – | – |
Full chart lists: App Store · Google Play.
Review momentum
ⓘ How we measure thisNew ratings a week
9.9
▼ -11% vs the 2 weeks before
Lifetime rating
4.7★
recent stars not readable yet: new ratings are a tiny share of the total
Review momentum
68/100
faster than 84% of Education apps
New ratings by country (5)
| Country | New ratings a week | Share | Last 2 weeks vs the 2 before |
|---|---|---|---|
 Canada | 2.5 | 32% | ▼ -29% |
 France | 2 | 25% | steady |
| United Arab Emirates | 1.2 | 15% | – |
 Saudi Arabia | 1.2 | 15% | – |
 India | 1 | 13% | – |
App Store ratings in the countries we track, 4-week average.
Review momentum (0-100) blends how fast the app collects ratings compared with other apps in its category (60%), whether that pace is speeding up (25%) and what recent raters give it (15%; recent stars well below lifetime pull it down). Ratings counts are read daily. A jump usually means a launch, a feature, ads or a new review prompt.
Ratings
Both stores. Store data, measured.
| Store | Rating | Ratings |
|---|---|---|
| App Store | 4.8 ★ | 170 |
| Google Play | 4.7 ★ | 19k 137 written reviews |
| Both stores | 4.7 ★ weighted by ratings | 19k |
About Scientific Calculator fx-991
Scientific Calculator fx-991 – The Ultimate Math & Science Tool!
Struggling with math problems, equations, or integrals? Need a powerful scientific calculator to solve step-by-step?
With Scientific Calculator fx-991, you can calculate, graph, and find formulas instantly – making learning math, physics, and chemistry easier than ever!
Key Features
+ Step-by-step equation solver – Enter any equation and get a detailed step-by-step solution.
+ Advanced scientific functions – Solve fractions, algebra, derivatives, integrals, trigonometry, and more.
+ Graphing mode – Visualize mathematical functions interactively.
+ Extensive formula library – Access key formulas for math, physics, and chemistry in seconds.
+ Unit converter – Quickly convert between different measurement units.
+ Casio fx-991 inspired interface – A familiar and intuitive experience for students.
Perfect for high school and college students, engineers, and professionals in STEM fields!
Who is this app for?
High school students – Solve algebra, calculus, and physics problems efficiently.
College & university students – Master engineering, physics, and complex math subjects.
STEM professionals – Perform advanced calculations quickly and accurately.
Download Scientific Calculator fx-991 now and simplify your calculations!
Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/.
Struggling with math problems, equations, or integrals? Need a powerful scientific calculator to solve step-by-step?
With Scientific Calculator fx-991, you can calculate, graph, and find formulas instantly – making learning math, physics, and chemistry easier than ever!
Key Features
+ Step-by-step equation solver – Enter any equation and get a detailed step-by-step solution.
+ Advanced scientific functions – Solve fractions, algebra, derivatives, integrals, trigonometry, and more.
+ Graphing mode – Visualize mathematical functions interactively.
+ Extensive formula library – Access key formulas for math, physics, and chemistry in seconds.
+ Unit converter – Quickly convert between different measurement units.
+ Casio fx-991 inspired interface – A familiar and intuitive experience for students.
Perfect for high school and college students, engineers, and professionals in STEM fields!
Who is this app for?
High school students – Solve algebra, calculus, and physics problems efficiently.
College & university students – Master engineering, physics, and complex math subjects.
STEM professionals – Perform advanced calculations quickly and accurately.
Download Scientific Calculator fx-991 now and simplify your calculations!
Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/.
Scientific Calculator fx-991 App Store
Scientific Calculator fx-991 gets 1k+ downloads a day worldwide (AppInsider estimate, November 2026, rounded down to a band).
Scientific Calculator fx-991 is #35 in Education Free in United Arab Emirates and charting in 2 of 30 countries we track.
Updated 8 Nov 2026 · rankings refresh through the day
DeveloperDinh Phuc
CategoryEducation
PriceFree
Released
Rating★ 4.8 (170)
Version1.9.3
Age rating4+
First seen by us 24 Sep 2026
24 Sep 2026Installs (est.)100k+ worldwide
Rating
4.8 ★
170 ratings
Measured
Best rank now
#35
Education FreeMeasured
New ratings a week
9.9
▼ -11% vs the 2 weeks before
Measured
Scientific Calculator fx-991 on the App Store
App details
App ID
1673640297
Publisher
Dinh Phuc
Publisher country
Vietnam
On the store since
Feb 2023
3 years on the store
Minimum OS
iOS 15.0+
iPhone 6s and later
Devices
iPhone · iPad
Universal purchase
Content rating
4+
Languages
59
AF SQ AR HY AZ EU BE BG CA HR CS DA …
Size
28 MB
Scientific Calculator fx-991 downloads
Worldwide, per day, and installs to date. The band is open; the exact number is free with an account.
How this is calculated
Apple publishes no download counts. App Store downloads come from chart positions and daily rating growth per country, calibrated on Google Play install counts; lifetime installs from ratings worldwide × installs per rating. Confidence is the chance the real number is within half to double ours.
Where Scientific Calculator fx-991's downloads come from Modelled
Last 30 days: organic search, browsing the store, features and paid ads.
Active users
All platforms, worldwide. Free with an account.
Stickiness (DAU / MAU)
how many monthly users open it on a given day
Retention · share of new users still active
Day 1
Day 7
Day 30
Time spent · per daily user
Average time spent Pro
min a day
Sessions a day Pro
Time per session Pro
min
How this is calculated
Monthly users come from lifetime installs across every store, fitted on monthly active user figures companies publish; daily users = monthly × the typical daily/monthly ratio for the category. Confidence is the chance the real number is within half to double ours.
In-app revenue
Worldwide, what users spend in Scientific Calculator fx-991 before Apple and Google take their fee.
How this is calculated
Not on any Top Grossing chart: monthly active users × spend per user for its category, measured on the charted apps nearest the bottom of the charts.
Business model: Subscription-led
How Scientific Calculator fx-991 makes money: subscriptions, one-off purchases and ads.
SubscriptionsIn-app purchasesAds · 1 ad networks
Subscriptions
/mo
of revenue
Ads
/mo
of revenue
Top in-app purchases · App Store US, most popular first
| 1 | Monthly Premium Access subscription | |
| 2 | HiEdu Pro Lifetime subscription | |
| 3 | Yearly Premium Access subscription | |
| 4 | Remove Ads 30 Days | |
| 5 | 6-Month Premium Membership subscription |
Where it ranks now
Every top chart it appears in across 30 countries.
| Country | Charts | Rank |
|---|---|---|
| United Arab Emirates | EducationFree | #35 |
| Saudi Arabia | EducationFree | #54 |
Apps near Scientific Calculator fx-991 on the chart
Education Free, around #35.
Ratings
App Store, worldwide.
Rating
4.8 ★
170 ratings
Measured
Ratings
170
Measured
Review momentum
ⓘ How we measure thisNew ratings a week
9.9
▼ -11% vs the 2 weeks before
Lifetime rating
4.7★
recent stars not readable yet: new ratings are a tiny share of the total
Review momentum
68/100
faster than 84% of Education apps
New ratings by country (5)
| Country | New ratings a week | Share | Last 2 weeks vs the 2 before |
|---|---|---|---|
| Canada | 2.5 | 32% | ▼ -29% |
| France | 2 | 25% | steady |
| United Arab Emirates | 1.2 | 15% | – |
| Saudi Arabia | 1.2 | 15% | – |
| India | 1 | 13% | – |
App Store ratings in the countries we track, 4-week average.
Review momentum (0-100) blends how fast the app collects ratings compared with other apps in its category (60%), whether that pace is speeding up (25%) and what recent raters give it (15%; recent stars well below lifetime pull it down). Ratings counts are read daily. A jump usually means a launch, a feature, ads or a new review prompt.
About Scientific Calculator fx-991
Scientific Calculator fx-991 – The Ultimate Math & Science Tool!
Struggling with math problems, equations, or integrals? Need a powerful scientific calculator to solve step-by-step?
With Scientific Calculator fx-991, you can calculate, graph, and find formulas instantly – making learning math, physics, and chemistry easier than ever!
Key Features
+ Step-by-step equation solver – Enter any equation and get a detailed step-by-step solution.
+ Advanced scientific functions – Solve fractions, algebra, derivatives, integrals, trigonometry, and more.
+ Graphing mode – Visualize mathematical functions interactively.
+ Extensive formula library – Access key formulas for math, physics, and chemistry in seconds.
+ Unit converter – Quickly convert between different measurement units.
+ Casio fx-991 inspired interface – A familiar and intuitive experience for students.
Perfect for high school and college students, engineers, and professionals in STEM fields!
Who is this app for?
High school students – Solve algebra, calculus, and physics problems efficiently.
College & university students – Master engineering, physics, and complex math subjects.
STEM professionals – Perform advanced calculations quickly and accurately.
Download Scientific Calculator fx-991 now and simplify your calculations!
Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/.
Struggling with math problems, equations, or integrals? Need a powerful scientific calculator to solve step-by-step?
With Scientific Calculator fx-991, you can calculate, graph, and find formulas instantly – making learning math, physics, and chemistry easier than ever!
Key Features
+ Step-by-step equation solver – Enter any equation and get a detailed step-by-step solution.
+ Advanced scientific functions – Solve fractions, algebra, derivatives, integrals, trigonometry, and more.
+ Graphing mode – Visualize mathematical functions interactively.
+ Extensive formula library – Access key formulas for math, physics, and chemistry in seconds.
+ Unit converter – Quickly convert between different measurement units.
+ Casio fx-991 inspired interface – A familiar and intuitive experience for students.
Perfect for high school and college students, engineers, and professionals in STEM fields!
Who is this app for?
High school students – Solve algebra, calculus, and physics problems efficiently.
College & university students – Master engineering, physics, and complex math subjects.
STEM professionals – Perform advanced calculations quickly and accurately.
Download Scientific Calculator fx-991 now and simplify your calculations!
Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/.
Latest updates
1.9.3
- Added Daily Challenge with 10 new math questions every day.
- Track your personal progress and compete on the 7-day leaderboard.
1.9.2
* Added one-variable polynomial division with quotient and remainder results.
* Improved the formula reference interface.
* Added the periodic table of chemical elements.
* Added the ability to save and manage favorite formulas.
* Improved performance and fixed minor bugs.
Scientific Calculator He-580 Android
Scientific Calculator He-580 gets 1k+ downloads a day worldwide (AppInsider estimate, November 2026, rounded down to a band).
Scientific Calculator He-580 is #67 in Education Free on Google Play in Vietnam and charting in 1 of 23 countries we track.
Updated 8 Nov 2026 · rankings refresh through the day
CategoryEducation
PriceFree
Released
Installs1M+
Rating★ 4.7 (19k)
Updated
Content ratingEveryone
Rating
4.7 ★
19k ratings
Measured
Best rank now
#67
Education FreeMeasured
Scientific Calculator He-580 on Google Play
App details
App ID
com.hiedu.calculator580
Publisher
DO DANG HUY
Publisher country
Vietnam
Content rating
Everyone
Scientific Calculator He-580 downloads
Worldwide, per day, and installs to date. The band is open; the exact number is free with an account.
How this is calculated
Google Play shows an exact lifetime install count; downloads per day are its daily change (measured). When Play hasn't refreshed the count, they come from new ratings and Top Free chart positions. Confidence is the chance the real number is within half to double ours.
Where Scientific Calculator He-580's downloads come from Modelled
Last 30 days: organic search, browsing the store, features and paid ads.
Active users
All platforms, worldwide. Free with an account.
Stickiness (DAU / MAU)
how many monthly users open it on a given day
Retention · share of new users still active
Day 1
Day 7
Day 30
Time spent · per daily user
Average time spent Pro
min a day
Sessions a day Pro
Time per session Pro
min
How this is calculated
Monthly users come from lifetime installs across every store, fitted on monthly active user figures companies publish; daily users = monthly × the typical daily/monthly ratio for the category. Confidence is the chance the real number is within half to double ours.
In-app revenue
Worldwide, what users spend in Scientific Calculator He-580 before Apple and Google take their fee.
How this is calculated
Not on any Top Grossing chart: monthly active users × spend per user for its category, measured on the charted apps nearest the bottom of the charts.
Business model: Subscription-led
How Scientific Calculator He-580 makes money: subscriptions, one-off purchases and ads.
SubscriptionsIn-app purchasesAds · 1 ad networks
Subscriptions
/mo
of revenue
Ads
/mo
of revenue
Top in-app purchases · App Store US, most popular first
| 1 | Monthly Premium Access subscription | |
| 2 | HiEdu Pro Lifetime subscription | |
| 3 | Yearly Premium Access subscription | |
| 4 | Remove Ads 30 Days | |
| 5 | 6-Month Premium Membership subscription |
Where it ranks on Google Play
Every top 200 chart it appears in across 23 countries.
| Country | Charts | Rank |
|---|---|---|
| Vietnam | EducationFree | #67 |
Apps near Scientific Calculator He-580 on the chart
Education Free, around #67.
Ratings
Google Play, worldwide.
Rating
4.7 ★
19k ratings
Measured
Ratings
19k
Measured
Written reviews
137
Measured
About Scientific Calculator He-580
Unleash the full potential of mathematics right at your fingertips with the HiEdu Scientific Calculator He-580. Tailored specifically for English-speaking students and professionals, this app is not just a calculator but a comprehensive mathematical tool designed to enhance your learning and problem-solving skills.
Key Features:
- Step-by-Step Solutions: Our standout feature is the Step-by-Step Solutions, meticulously optimized for various educational curriculums and languages. This function breaks down complex mathematical problems into understandable steps, mirroring the way they are taught in classrooms. It's like having a personal tutor that guides you through each calculation, ensuring a deeper understanding of mathematical concepts.
- Versatile Computing Abilities: Whether it's basic calculations or advanced functions like fractions, percentages, complex numbers, vectors, and matrices, the HiEdu Calculator handles them with ease. Its versatility makes it ideal for a wide range of users, from high school students grappling with algebra to engineers solving intricate equations.
- Natural Display Interface: Our intuitive interface displays mathematical expressions as they appear in textbooks, making it easier to enter and understand complex formulas.
- Graphing Tools: Visualize mathematical concepts with our powerful graphing feature. Plot functions and analyze equations graphically for a better understanding of their behavior.
- Comprehensive Formula Library: Access an extensive collection of mathematical and physical formulas. This feature is invaluable for students and professionals alike, providing quick references and aiding in problem-solving.
- Unit Conversion Toolkit: Convert between various units like currency, weight, area, volume, and length with our easy-to-use conversion tool, making this app a practical companion in various fields of study and work.
Optimized for the English-speaking audience, the HiEdu Scientific Calculator He-580 stands out with its user-friendly design and tailored educational content. It's not just an app; it's your partner in the journey of mastering mathematics and related fields. Elevate your learning experience with the HiEdu Scientific Calculator He-580 – your smart solution to complex mathematical challenges.
Key Features:
- Step-by-Step Solutions: Our standout feature is the Step-by-Step Solutions, meticulously optimized for various educational curriculums and languages. This function breaks down complex mathematical problems into understandable steps, mirroring the way they are taught in classrooms. It's like having a personal tutor that guides you through each calculation, ensuring a deeper understanding of mathematical concepts.
- Versatile Computing Abilities: Whether it's basic calculations or advanced functions like fractions, percentages, complex numbers, vectors, and matrices, the HiEdu Calculator handles them with ease. Its versatility makes it ideal for a wide range of users, from high school students grappling with algebra to engineers solving intricate equations.
- Natural Display Interface: Our intuitive interface displays mathematical expressions as they appear in textbooks, making it easier to enter and understand complex formulas.
- Graphing Tools: Visualize mathematical concepts with our powerful graphing feature. Plot functions and analyze equations graphically for a better understanding of their behavior.
- Comprehensive Formula Library: Access an extensive collection of mathematical and physical formulas. This feature is invaluable for students and professionals alike, providing quick references and aiding in problem-solving.
- Unit Conversion Toolkit: Convert between various units like currency, weight, area, volume, and length with our easy-to-use conversion tool, making this app a practical companion in various fields of study and work.
Optimized for the English-speaking audience, the HiEdu Scientific Calculator He-580 stands out with its user-friendly design and tailored educational content. It's not just an app; it's your partner in the journey of mastering mathematics and related fields. Elevate your learning experience with the HiEdu Scientific Calculator He-580 – your smart solution to complex mathematical challenges.
What's new in 1.8.6
✨ Updated the formula interface and added the Periodic Table.
❤️ Added favorite formulas and recently viewed formulas.
⚡ Improved calculation history for faster viewing and access.
❤️ Added favorite formulas and recently viewed formulas.
⚡ Improved calculation history for faster viewing and access.