Nor-Cal Hobbies "Gears" app is an R/C car and truck gear ratio and rollout calculator. Enter the transmission ratio, spur, and pinion to generate a table of gear ratios. Enter the tire diameter to get a table of rollouts. Designed for the R/C car or truck racing nut looking for a super easy way to determine gearing on your Android phone right at your pit table.
Seamusoft is the developer of the tool that can be found in the Productivity category. Over 10K users set up this application and the most recent update was released on Jun 29, 2015. People rated the app 4.6 on Google Play.
A free .apk installation package of Nor-Cal Hobbies Gears 1.0.3 can be downloaded from Droid Informer and you can have a look at users' reviews on this site. Prepare 88 KB of free space on your device for this app installer and keep in mind that it runs on Android 2.2 and higher. The antivirus report shows that the app is totally safe.