Question

Is there a difference between developing for a smartphone vs for a tablet? i.e. iPhone vs iPad, Android vs Android Tablet. What are the main differences to take into account? I know its a broad question, but trying to wrap my head around the difference.

Edit:
If a company can develop for iPhone apps, does that mean that the company could easily develop for iPad as well? Do companies specialize in iOS smartphones and not iOS tablets?

Answer 1

One of the best answers is from what you’ll find on developer.android.com

Each screen size offers different possibilities and challenges for
user interaction, so in order to truly satisfy and impress your users,
your application must go beyond merely supporting multiple screens: it
must optimize the user experience for each screen configuration.

Usually the programming is the same the only change is layout and maybe a few extra buttons or less buttons.