To many dwellers stacking up behind one person, making it solid to heal. Also struggle to select certain dwellers while in the process of healing. Also major lag the more population we have... NOT just happening to me its the same with friends and family. P.s is there actually any point in dwellers moving in battle. < plays a huge roll in the problem >. ( "?)
I agree with the stacking problem. As for the lag, it gets unbearable on my iPhone 6 when I send out more than 30 dwellers to the wasteland. My game crashes when I scroll through the dweller list for the wasteland around 20 or so.