Feels like a scam

Paid for this app. Tried to use it and was immediately offered a deal to upgrade to the full version for $9.99. Ignored the deal and went to the top 100 picked a song and could see it no problem. Pressed the play button and again asked to upgrade to the full version. What happens when I upgrade. Will I be asked to upgrade again? I dont trust anyone who does business like this. I wont be using this app again even though I paid money for it. Check YouTube. There are lots of good channels with free video instruction. Try JustinGuitar Songs.

RMcKinnon about Ultimate Guitar: Chords & Tabs, v2.6.2