How to Know If You Really Do (or Don't) Need a Mobile App

Google Play Store has more than 3.5 million apps and Apple has over 2.2 million. In other words, the market for mobile apps is huge, given that a majority of people consume information and buy various products via smartphones.

This is a companion discussion topic for the original entry at

For a new startup, how do you choose whether to go ahead with android, iOS or both platforms?

What are some leading software development companies who can help a new startup build mobile apps?