Mighty Tracker app for iPhone and iPad

This app allows you to track your time when working.

It supports creating multiple Groups, so that you can track times for "work", "hobby", "sport" or anything else.
If you have different hobbies, sport activities, or projects at work then the MyTime App also allows you to have multiple "Projects" inside of a Group. This makes it possible to work on different projects and track your times individually for each project.
Each Project offers you two options to track your time: Firstly it has a built in timer, that you can start when you start your activity and stop when you finished your activity. All thats left in that case is adding a description and you are good to go. Secondly, you can track times manually, in case you missed to start the timer.

Additionally, you get an overview of all your tracked times inside a project in a grouped-by-month list.