Lessons learned building the second version of FriendTime

First validate: Keep the feature-set simple.

Because I wanted too much for the first version, it took me more than a month to build. Because I set too high goals for the FIRST Version, I started doubting the product and gave up. When trying to continue half a year later, I had to greatly simplify the product, and still it was a lot of work to get the app working again.

Monetise after it's validated, not during.

In production I figured out that the app wasn't that good. The monetisation made the app take a lot more time to build. After it was sort of done, I found out the app wasn't good enough.

The final touch takes the most time.

This is probably the most important lesson. Make sure you don't underestimate how long something will take. Every extra feature will cost a lot more time compared to the time you estimate it to cost. Iterations make sure it takes twice as long to perfect it.

Write code well, not fast.

Reading code that isn't well organised half a year later is hard.