I got RemotePilotStudyBuddy a few weeks before I took my part 107 remote pilot test, which I passed with an 82%. I used RemotePilotStudyBuddy, some free practice tests online, and a few YouTube videos. I probably spent around 20 hours total studying. This is the only app I paid for, and I think it was worth it. On RemotePilotStudyBuddy, I mostly used the practice tests. There were a lot of questions on the test that were very similar to the ones in the practice tests in RemotePilotStudyBuddy . When taking a practice test, I like that you get the answers to the questions, as well as an explanation. I also liked the materials provided for study- however, my eyes could not read most of the documents for very long on an iPhone.