Many people are wondering why Gmail, a service launched in April 2004, is still in beta. The screenshots below are a good answer. Gmail still has problems with scalability and server errors are still frequent.
How to use Gmail efficiently
When will you run out of Gmail storage space?
Gmail - the fourth most popular webmail service
AOSP changelog posted for Android Nougat v7.0.0_r1 (NRD90M)
21 minutes ago