My daughter was signed in as a guest. I read through the LINE FAQs completely right when I installed the app for her. It stated clearly that if the game was deleted you can regain your data by simply reinstalling the app. Anyway, after spending over $100 on in-app purchases, the game accidentally got deleted. I reinstalled the game...NO DATA. I contacted LINE repeated and got the runaround. I pointed out what it states in the FAQs. Anyway, they never supplied me with any sort of compensation. They did however, change their FAQs!! I'm still trying to deal with them, Apple, and Disney. Such shady business practices. Reading through similar posts, they have cheated users out of $1000s.
This is what the LINE FAQs stated on June 29, 2015:
I accidentally deleted the LINE: Disney Tsum Tsum app. What should I do?
If you delete the app, you can play again using your old data by simply re-installing the app. However, if you were playing the game using your LINE ID, you must be sure to sign in using LINE Login after re-installing the app.
And this is what they changed it to after my repeated efforts to get compensated for my lost data and bringing it to their attention what it states in their FAQs (as of July 26, 2015):
I accidentally deleted the LINE: Disney Tsum Tsum app. What should I do?
If you had been playing using a LINE Login, even if you have deleted the app, your data will still carry over when you reinstall the app. Please be sure to sign in using your LINE Login after re-installing the app.
*Please note that if you had been playing using a Guest Login, you will not be able to carry over your old data if you uninstall and reinstall the app.