CDL Prep: iPhone vs Android
CDL Prep by Jeffrey Diaz is on both the App Store and Google Play. Here are both versions together: downloads, users, revenue, ratings and chart positions, store by store with totals.
Rating
4.6 ★
13k ratings, both stores
Measured
Best rank now
#85
Android · 
Education Free
Education FreeMeasured
App Store
App details
App ID
1101536521
Publisher
Jeffrey Diaz
Publisher country
United States
Minimum OS
iOS 15.0+
Content rating
4+
Languages
1
EN
Size
7 MB
Google Play
App details
App ID
com.jeffreydiaz.android.app.cdlprep
Publisher
Jeffrey Diaz
Publisher country
United States
Content rating
Everyone
CDL Prep downloads & installs
Both stores, worldwide. Bands are open; exact numbers are free with an account.
| Store | Downloads / day | Lifetime installs |
|---|---|---|
| iPhone | – | – |
| Google Play | – | 1M+ Measured |
| Total | – | 1M+ Confidence |
How this is calculated
iPhone: 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 CDL Prep'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.
Business model: Ad-led
How CDL Prep makes money: subscriptions, one-off purchases and ads.
Ads · 1 ad networks
Ads
/mo
of revenue
Where it ranks now
Both stores, across every country we track.
Ratings
Both stores. Store data, measured.
| Store | Rating | Ratings |
|---|---|---|
| App Store | 4.7 ★ | 6.9k |
| Google Play | 4.6 ★ | 5.7k 2.8k written reviews |
| Both stores | 4.6 ★ weighted by ratings | 13k |
About CDL Prep
CDL Prep is the best way to prepare for the Commercial Drivers License General Knowledge, and various endorsement exams. CDL Prep contains questions on the following topics: General Commercial, Air Brakes, Combinations, Hazmat, Passenger, Tanks, School Bus, and Doubles/Triples.
Features:
1. Over 500 questions to practice with.
2. Exam Mode - 60 minutes to answer 50 randomly chosen questions, or 40 minutes to answer 20 to 30 questions on endorsement topics. At the end, review your score and any incorrect answers.
3. Practice Mode - Answer questions and receive instant feedback if you answered incorrectly.
4. Answer Randomization - Answers to questions will not always be in the same position.
Please send any feedback or request to: [email protected]. Thank you for reading, and good luck on your exams!
Features:
1. Over 500 questions to practice with.
2. Exam Mode - 60 minutes to answer 50 randomly chosen questions, or 40 minutes to answer 20 to 30 questions on endorsement topics. At the end, review your score and any incorrect answers.
3. Practice Mode - Answer questions and receive instant feedback if you answered incorrectly.
4. Answer Randomization - Answers to questions will not always be in the same position.
Please send any feedback or request to: [email protected]. Thank you for reading, and good luck on your exams!
CDL Prep iPhone
CDL Prep is #98 in Education Free in United States and charting in 1 of 24 countries we track.
Updated 27 Sep 2026 · rankings refresh through the day
DeveloperJeffrey Diaz
CategoryEducation
PriceFree
Released
Rating★ 4.7 (6.9k)
Version9.13
Age rating4+
First seen by us 25 Sep 2026
25 Sep 2026Rating
4.7 ★
6.9k ratings
Measured
Best rank now
#98
Education FreeMeasured
CDL Prep on the App Store
App details
App ID
1101536521
Publisher
Jeffrey Diaz
Publisher country
United States
Minimum OS
iOS 15.0+
Content rating
4+
Languages
1
EN
Size
7 MB
CDL Prep 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. iPhone 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 CDL Prep'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.
Business model: Ad-led
How CDL Prep makes money: subscriptions, one-off purchases and ads.
Ads · 1 ad networks
Ads
/mo
of revenue
Where it ranks now
Every top chart it appears in across 24 countries.
| Country | Charts | Rank |
|---|---|---|
| United States | EducationFree | #98 |
Apps near CDL Prep on the chart
Education Free, around #98.
Ratings
App Store, worldwide.
Rating
4.7 ★
6.9k ratings
Measured
Ratings
6.9k
Measured
About CDL Prep
CDL Prep is the best way to prepare for the Commercial Drivers License General Knowledge, and various endorsement exams. CDL Prep contains questions on the following topics: General Commercial, Air Brakes, Combinations, Hazmat, Passenger, Tanks, School Bus, and Doubles/Triples.
Features:
1. Over 500 questions to practice with.
2. Exam Mode - 60 minutes to answer 50 randomly chosen questions, or 40 minutes to answer 20 to 30 questions on endorsement topics. At the end, review your score and any incorrect answers.
3. Practice Mode - Answer questions and receive instant feedback if you answered incorrectly.
4. Answer Randomization - Answers to questions will not always be in the same position.
Please send any feedback or request to: [email protected]. Thank you for reading, and good luck on your exams!
Features:
1. Over 500 questions to practice with.
2. Exam Mode - 60 minutes to answer 50 randomly chosen questions, or 40 minutes to answer 20 to 30 questions on endorsement topics. At the end, review your score and any incorrect answers.
3. Practice Mode - Answer questions and receive instant feedback if you answered incorrectly.
4. Answer Randomization - Answers to questions will not always be in the same position.
Please send any feedback or request to: [email protected]. Thank you for reading, and good luck on your exams!
Latest updates
9.13
Minor bug fixes and grammatical corrections.
CDL Prep Android
CDL Prep is #85 in Education Free on Google Play in United States and charting in 1 of 15 countries we track.
Updated 27 Sep 2026 · rankings refresh through the day
DeveloperJeffrey Diaz
CategoryEducation
PriceFree
Released
Installs1M+
Rating★ 4.6 (5.7k)
Updated
Content ratingEveryone
Rating
4.6 ★
5.7k ratings
Measured
Best rank now
#85
Education FreeMeasured
CDL Prep on Google Play
App details
App ID
com.jeffreydiaz.android.app.cdlprep
Publisher
Jeffrey Diaz
Publisher country
United States
Content rating
Everyone
CDL Prep 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 CDL Prep'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
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.
Business model: Ad-led
How CDL Prep makes money: subscriptions, one-off purchases and ads.
Ads · 1 ad networks
Ads
/mo
of revenue
Where it ranks on Google Play
Every top 200 chart it appears in across 15 countries.
| Country | Charts | Rank |
|---|---|---|
| United States | EducationFree | #85 |
Apps near CDL Prep on the chart
Education Free, around #85.
Ratings
Google Play, worldwide.
Rating
4.6 ★
5.7k ratings
Measured
Ratings
5.7k
Measured
Written reviews
2.8k
Measured
About CDL Prep
CDL Prep is the best way to prepare for the Commercial Drivers License General Knowledge, and various endorsement exams. CDL Prep contains questions on the following topics: General Commercial, Air Brakes, Combinations, Hazmat, Passenger, Tanks, School Bus, and Doubles/Triples.
Features:
1. Over 500 questions to practice with.
2. Exam Mode - 60 minutes to answer 50 randomly chosen questions, or 40 minutes to answer 20 to 30 questions on endorsement topics. At the end, review your score and any incorrect answers.
3. Practice Mode - Answer questions and receive instant feedback if you answered incorrectly.
4. Answer Randomization - Answers to questions will not always be in the same position.
5. Performance tracking - Review your performance on every question. Red = You have an average score less than 70%, Orange = You have an average score between 70-89%, Green = You have an average score of 90% and above.
Please send any feedback or request to: [email protected]. Thank you and good luck on your exams!
Features:
1. Over 500 questions to practice with.
2. Exam Mode - 60 minutes to answer 50 randomly chosen questions, or 40 minutes to answer 20 to 30 questions on endorsement topics. At the end, review your score and any incorrect answers.
3. Practice Mode - Answer questions and receive instant feedback if you answered incorrectly.
4. Answer Randomization - Answers to questions will not always be in the same position.
5. Performance tracking - Review your performance on every question. Red = You have an average score less than 70%, Orange = You have an average score between 70-89%, Green = You have an average score of 90% and above.
Please send any feedback or request to: [email protected]. Thank you and good luck on your exams!
What's new in 9.13
Minor bug fixes and grammatical corrections.