Retention is not difficult to measure. You essentially track how often a user comes back over 1 day, 3, 7 days, 15, 30 days, etc, and benchmark against your co

Retention is not difficult to measure. You essentially track how often a user comes back over 1 day, 3, 7 days, 15, 30 days, etc, and benchmark against your competitors. The hard part is figuring out why your numbers are low and why the drop-off is happening, and coming up with creative solutions to solve the problems. In addition to Net Promoter score, consider tracking K-Factor for virality, which is way more objective, and might give you some hints on what your NPS score is.