I don't know how to check that, but i don't think so...

I'm not an expert but I think it depends on what are your needs. If you need the app to be done quickly without including any complex task (such as accelerometer/gps/3D graphic features) hybrid might be the way, because with some frameworks you can build three apps for the most famous OSs by writing the code just once . On the other hand native apps have more performance and allow you to include powerful and specific features. It's up to you to choose the right way to build your app/system. Talking about Web Apps I think they're necessary only if your users connect to your service throughout PCs; Web Apps via smartphone usually are slower and sometimes more annoying than normal apps. I repeat: I'm not an expert, I'm talking through my personal opinion and experience. I'll be glad if someone would like to correct me.

Thank you man, this will help a lot (because my boss bought some udemy courses but I prefer reading than listening), but I would like to know what are common mistakes that occur the first times people use it and things like that...