After 3 Months, I am very happy with N26
I have opened a Bank account at N26, October 2019 as a non-EU citizen expert residing in Germany. After testing couple of months, I've moved my main savings to my N26 account. So far compare to other German Banks, I must say that N26 provides a much more professional service even better than Deutsche Bank. 

If you are expert moving to Germany and interested in online banking then this is the right place for you. To sum up everything:

N26 is brilliant because:
-Super fast internet banking + modern user interface
-If you are non-EU, other Germans bank may reject opening an account to you. N26 has no such discrimination policy.
-Gives you good portfolio and money management spaces
-Opening an normal account is free
-Unlike other German banks it has no unmentioned service fees

What N26 needs to improve:
-With normal account you can withdraw only 5 times from ATM
-It has no EC Karte but only debit card which might be quite tricky if you ever end up in small German towns where they only take cash or EC-Karte.

Overall: I am highly satisfied.