You need to subscribe to store any test results, notes, etc.
Once you subscribe, you can have the app on multiple devices. I have it on my iphone, ipad, and laptop as a Microsoft App. The data syncs between them. You can also share your Poolmath data logs here on the forum so if you have questions we can easily see your data. Hover your mouse over my Member name, you will see PoolMath Logs. Select it and you can see my data.