Nir Eyal

The cold truth is that the best products don't always win. Many times it's - the products that have the ability to keep users coming back and using them without conscious thought and using them out of habit are the ones that keep us coming back.

The market for religious apps is fiercely competitive; searching for 'bible' in the Apple App Store returns 5,185 results. But among all the choices, YouVersion's Bible, funded by LifeChurch.tv of Edmond, Oklahoma, seems to be the chosen one, ranking at the top of the list and boasting more than 641,000 reviews.

In my office in Jerusalem, there's an ancient seal. It's a signet ring of a Jewish official from the time of the Bible. The seal was found right next to the Western Wall, and it dates back 2,700 years, to the time of King Hezekiah. Now, there's a name of the Jewish official inscribed on the ring in Hebrew. His name was Netanyahu.

The Gmail app is definitely the app I use the most. I am always running from meeting to meeting, so it keeps me up-to-date with everything going on. I actually e-mail more often from my iPhone than my laptop, so having a nicely designed e-mail app is really important.