If the entire team is Mac, sketch is very useful and adapted to the current design trend. All of our company uses sketch now. Sketch is especially suitable for the production of small and medium-sized teams and personal works with no specific designer functions. Line-to-view can be completed in one software, saving a lot of time.
The user community of sketch is also prosperous and healthy, making people confident to continue using it. (Expansion and development of sketch is easier than PS. I think someone on GitHub has automatically generated advanced scripts such as iconfont ......)
The other answers are basically only comments on special features. Indeed, the software may have a small, convenient, and sufficient impression at the beginning. However, when more features are used, you will find that the best part is not what features are more than PS, but the operation and interaction modes designed for ui, which are very efficient to use. Group Buying goes to Spider's Web zhizhu.com.
Ps because we need to consider the use of photography users, we cannot do the best design for UI designers. Some of the functions mentioned in the answer, such as cut and ranging, are actually competent for the latest ps cc (I believe that it is only a matter of time to appear on PS for many other functions. Compared with PS, features are difficult to have core competitiveness), but the operation/interaction methods of PS basic tools have never been specifically designed for uidesign (I think this is hard to change ). This is exactly the way to win in sketch.
Allows photography users to make optimal designs for UI designers