Hello everyone
Buy original or branded power bank. If you are looking a good power bank I suggest you check your smart phone battery capacity, mobile input amp like 1A or 2A.
If you have 2500mah battery you can buy 10000 mah or more. If you are a traveller or you need extra power absence of electricti
You can purchase 20000 mah or more.
Check power bank input output and battery capacity according to your mobile capacity.