I am a special education teacher and I love Boom for data. If your students have their own individual login it works the best. If you have a google classrrom they can login with their google login. It is a little more set up for you but works well for kids.
On ipads, each student has to log and if you are sharing an ipad for many kids than you need individual logins and each kid needs to remember to log out., I think I have several logins saved. I use the picture logins. Sometimes the security bar will block it so then you have to turn the ipad long ways and close the security box. Then it will work. (that part is a pain)
Fast plays don't collect data.
I hope that helps.
Check out my store Tisher's Class for lots more decks geared towards students in special education.
On some the ipads I use in my class, I can not log in students. The app will not bring up the keyboard. Thus I can't type in the student's password. Thus can't log them in. We can do the fast play, but then I don't get data. This is very frustrating, because that is the whole reason I spent my money on this system. I need Data for IEP's