Timesheet tracks the times you spend on your various jobs. Track "live" or manually. See total duration, costs per customer/project. CSVExport. Calendar export. This is the full version, free and open source. Permission used to read date formats, calendar, and export to sdcard.
OpenIntents is the creator of OI Timesheet which can be found in the Productivity category. The latest release was on Jun 13, 2017 and the tool was downloaded and set up by over 10K users. This application has been rated 3.8 on Google Play.
It's free of charge to download the installer of OI Timesheet, also, you can take a look at users' reviews on Droid Informer. The app runs on Android 2.3 and above. The app is totally secure for downloading.