How long would it take two developers working full time to create an iOS app like Tinder?

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.

My 2 favourite are: - www.uxpin.com - www.flinto.com Flinto is by far my favorite for mobile. I also us www.balsamiq.com for anything wireframe. Sometimes I jump into Sketch http://www.bohemiancoding.com/sketch/ for more high fidelity mockups using their Mirror feature http://www.bohemiancoding.com/sketch/mirror/ Hope that helps. P.S. There's a tonne of Mobile UX experts on Clarity, many $1/min - call them, you'll learn so much. my2cents.

You are right that the range is wide. You need to figure what are good values to have for your category. Also, you can focus on the trend (is your DAU/MAU increasing vs decreasing after you make changes) even if benchmarking is tough. Unless your app is adding a huge number of users every day (which can skew DAU/MAU), you can trust the ratio as a good indication of how engaged your users are. For games, DAU/MAU of ~20-30% is considered to be pretty good. For social apps, like a messenger app, a successful one would have a DAU/MAU closer to 50%. In general most apps struggle to get to DAU/MAU of 20% or more. Make sure you have the right definition of who is an active user for your app, and get a good sense of what % of users are actually using your app every day. Happy to discuss what is a good benchmark for your specific app depending on what it does.

Apps are difficult to fund on IndieGoGo as few are successful, and we rarely take them on as clients. Websites like http://appsfunder.com/ are made for that very reason, but again, difficult to build enough of a following willing to pay top dollar for an app that could very well be free, already existing in the marketplace. A site that is gaining more traction you may want to look into would be http://appsplit.com/. Again, Appsplit Is Crowdfunding For Apps specifically.