Kotak bank mobile application is a good in all the basic banking function. You can access all your different accounts in one app. You can transfer money without having to add beneficiary. User interface is also quite good and handy. Response is decent. Customer care options can be improved like chats / call me options. Still there are certain things that can not be done through app like adding beneficiary.
Investment account interface is also quite good and easy to understand. Search option for mutual fund list can be provided. In all better app than what I use for SBI.