Hello, I am new on these forums but I hope I can learn from you guys and share my expertise as well.
As for the domains, I would go with .com Whatever people may say about .net and .org, those two dudes are not even close to .com authority for Google. I had a similar question a while ago when I ordered an application development from one comapany (I
found it here) and so after they made it, I decided to build a site around the app. I was checking many domain names and also the competitors of the app and what I found was that all the high-ranked sites for my keywords were in the .com zone.
It's up to you but I hope it helps,
Feel free to contact me should you have any more questions.