Currently it can track when you changed batteries and calculate how long they will last. The calculation is done based on the former times the batteries were changed.
The location of a device is currently not part of the app. But I will write it on the roadmap. Hier world you wish this world work?

Are this problems you have now without the app or while using the app?

You can choose from pre-defined battery types or add your own. The homescreen widget provides a quick overview of devices that may need new batteries soon. Best of all, your data is automatically synced via iCloud, ensuring your privacy.