Can you offer 1-month or 1-week trials on in-app purchases?

There are two sides to that question. One is the mobile app itself and the other is the backend. If I misunderstood in any way and you didn't mean "native" app I apologize in advance. On the backend, there is no clear cut answer to which is the "best". It depends solely on the developers you are able to get. We for example use Node.js , mongoDB, redis, elasticsearch and a couple of proprietary tools in the backend. But you have your pick of the litter now both on the backend api and the datastore with the myriad of options available and touted as the "best" currently on the market. Now on the app side again it solely depends on what you need your mobile app to do. Experiencing first-hand "develop once, run anywhere" I can say it's more like "develop once, debug everywhere" to quote a Java saying. We have tried Phonegap and Titanium Appcelerator and we have switched to native (ObjC and Java) after a couple of months of trying to go the hybrid route. The reasons behind the choice are as follows: - anything that breaks the pattern of how those frameworks NEED to operate is just a huge technical debt that keeps accruing a huge interest. - anything that uses css3 accelerated animations on Android is buggy at best and slow as hell at worst on any lower (< 4.1 I think) versions of Android I hope this gives you some insight. If you need/want to ask me anything feel free to contact me. Mihai

Well, the biggest cost here wouldn't be in the app, but in the server infrastructure. As usual with connected apps, people often forget they have to be connected to servers. The app itself is just a view to what the servers provide, so it's not the major cost. 20K $ to 100K $ should be enough. On server stuff, I expect it to be a lot more, particularly if you aim for a wide audience (several million $). On a Whatsapp clone, I'd consider: - solutions for performing calls through servers, not that easy. Look at what Twilio provides. WebRTC is an upcoming protocol that will ease that (web & mobile). - solutions for API, IM and user accounts management. Look at StackMob or Parse which are MBaaS (Mobile Backend as a Service). Hope it helps!

Apple will allow a developer to register 100 UDID devices per 12 month cycle to test via TestFlight or HockeyApp. Having started with TestFlight, I would really encourage you NOT to use it, and go directly to HockeyApp. HockeyApp is a much better product. There is also enterprise distribution which allows you far more UDID's but whether you qualify for enterprise distribution is difficult to say. As part of your testing, I'd encourage to explicitly ask your testers to only register one device. One of the things we experienced was some testers registering 3 devices but only used one, essentially wasting those UDID's where we could have given to other testers. Who you invite to be a tester should be selective as well. I think you should have no more than 10 non-user users. These people should be people who have either built successful mobile apps or who are just such huge consumers of similar mobile apps to what you're building, that they can give you great product feedback even though they aren't your user. Specifically, they can help point out non obvious UI problems and better ways to implement particular features. The rest of your users should be highly qualified as actually wanting what you're building. If they can't articulate why they should be the first to use what you're building, they are likely the wrong tester. The more you can do to make them "beg" to be a tester, the higher the sign that the feedback you're getting from them can be considered "high-signal." In a limited beta test, you're really looking to understand the biggest UX pain-points. For example, are people not registering and providing you the additional permissions you are requiring? Are they not completing an action that could trigger virality? How far are they getting in their first user session? How much time are they spending per user session? Obviously, you'll be doing your fair share of bug squashing, but the core of it is around improving the core flows to minimize friction as much as possible. Lastly, keep in mind that even with highly motivated users, their attention spans and patience for early builds is limited, so make sure that each of your builds really make significant improvements. Happy to talk through any of this and more about mobile app testing.

I would suggest launching in a foreign app store only (ex: Canada). That will allow you to get more organic users to continue iterating without a big push. I got this idea from Matt Brezina (Founder of Sincerely, previously Xobni) https://clarity.fm/brezina - he's the man when it comes to testing & iterating mobile apps.

I developed and published mobile apps as an individual for several years, and only formed a corporation later as things grew and it made sense. As far as Apple's App Store and Google Play are concerned, you can register as an individual developer without having a corporation. I'd be happy to help further over a call if you have any additional questions. Best of luck with your mobile app!