There are many other wallets that are also offering staking features for different altcoins that they have. It's just you need to choose the reputable on those wallets that also has that feature.
It easy to choose from those available wallets that have staking feature too.
Exchange wallet are not safe to use as staking mate, though others has offering staking yet we are always being advised that we need to stay away from leaving our money in online wallets for long time.
It's upon the discretion of the person who's about to stake his/her funds. Many are encouraged to do that into exchanges staking because APYs are quite good enough for them and they really think that they're safe with those reputable exchanges but I call it 50/50.
I will only let my funds in wallets when there are a need to trade .
Online wallets, this is what I guess you're trying to say.