Stargazer and Lobstr, are most popular ones, yet they too have their flaws. Lobstr asks for an e-mail address, what actually takes away one of cryptocurrency benefits - anonymity/ pseudonymity. Stargazer, there again doesn’t backup the seed or import a seed from another backup. The one I’m using is Pegasus Wallet. It’s actually still pretty new, it was released about 5 months ago. Yet, in my opinion it is very well thought - through, in all important aspects.