4 stars: I'd like to give it five stars just because it is so versatile and low-cost. But the interface is confusing, and it's hard to do certain things. It seems hard to edit or combine contacts, and it's puzzlingly impossible to delete unwanted contacts and parts of history. The usability of the interface really deserves two stars, and it needs a usability redesign.
3 stars: The app is mostly fine, save for a couple problems. Video calls are laggy at the best of times, occasionally unbearably so. To make it worse, the last update, in which Microsoft added 'stability improvements' seems to have completely broken the skype contact list. I have not been able to access my skype contacts, have not been able to regulate group chats, and have not been able to save new contacts. The app is inconsistent at best.
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