The 2 may have different setting , where one was set in some deserted Island , while the other one was set in the future , but the goal were still the same which the group have to work together in order to survive.
1. The same story plot where student were stranded and have to face the reality that they have to survive.
2. The same character plot where each has it's own specialization.
3. The same adventure that them characters experiences, as they go on living.
1. One was more like a sic-fi, adventure type while the other was more of ecchi , comedy and josie thing.
2. One was more of a all girls sorority, while the other one was a mixed of boys and girls.
3. One was more of a serious thing while the other was more like a slice of life thing.
Animes that consist on a group of girls surviving day-to-day in the hostilities of their environments which are wasted lands, abandoned factories, desert islands.
In Girls' Last Tour is much more dramatic since the civilization has collapsed there and Chito and Yuu are almost the last two persons still alive, while in Are You Lost? has more comedy, included some tutorials for camping, and also a small dose of ecchi.
Both series have the straight-woman, Chito and Homare in Shoujo Shuumatsu Ryokou and Sounan Desu ka? respectively; and the clumsy girl(s), Yuuri, and Asuka, Mutsu and Shion in SSR and SDK respectively.
Both anime has a all female cast which are all beautiful and have their own personalities. Both anime also has some lesson, Dumbnell teach us how to exercise, and Sounan Desu ka teaches us about survival. Both anime are also funny as hell.