As others have mentioned, YAGNI[0]. You have to avoid the tempting sirens call and wait until you actually have scaling problems, before anyone can tell you how

As others have mentioned, YAGNI[0]. You have to avoid the tempting sirens call and wait until you actually have scaling problems, before anyone can tell you how to solve them. Make sure you follow "best practices" in whatever parts of the app you're building. Also try to have some good instrumentation in place, like New Relic for server usage/app performance and Sentry/Bugsnag/etc for catching exceptions if/when those happen. If it's mostly a client-side app that runs on someone's phone, then there really is no central scaling bottleneck. If you're worried about scaling the backing API, I'd start with one of Amazon's Elastic Load Balancers and put two micro EC2 servers behind it. If you get a ton of traffic, you can easily take one server out to increase its size without bringing the app down, or you can just add more micro/small servers and scale horizontally. [0]: http://en.wikipedia.org/wiki/You_aren%27t_gonna_need_it http://en.wikipedia.org/wiki/You_aren%27t_gonna_need_it