How to clear the progress on Clash Royale

As I understand it, if you authorize Google Play for her phone and you're OK with her using your account and having access to all of you downloads and payment method, then there shouldn't be an issue. If a piece of content has an activation limit, it will typically tell you. For instance I have purchased a backup application but it can only be active and installed on one device at a time. For the most part I believe Google leaves the limit selection up to the individual developer.

But, Google did recently implement a 10 device limit as you can read here:

http://support.google.com/googleplay/bin/answer.py?hl=en&answer=1230356&topic=2450456&ctx=topic

You'll see tighter limits more active in the music and video areas as you can see here videos have a 5 device install limit, but can only be played by one device at a time:

http://support.google.com/googleplay/bin/answer.py?hl=en&answer=2666462

If you have already used your one sync, then you are kind of stuck. When switching devices, they allow you only one sync. This is for security reasons, but it kind of acts as an inconvenience here. There is almost no way to get your account synced after that. I would recommend contacting Supercell if you are desperate.