Keeping things simple, you can use this app to track both your current Playoffs or add in past results that you may still have and get a look at your progress.
*History*
See a list of all your previous attempts, and tap on an entry to view your individual scores.
Above the list, there is a graph, by default showing your scores, but that can be changed to any individual exercise, to see how your chin-ups are progressing.
*Profile*
All data is stored locally, and offline, and user profiles are available for those who want online backup and access to your scores on multiple devices. Once logged in, your data will be uploaded and then become available to any other device you log into afterwards.
Account or not, you will always be able to back up your data locally yourself, this can then be restored on another device.