I presume you want a never locked smartphone, without any contract
You have a lot of options to choose, according to your preferences:
Xperia M2, featuring a 8MP camera, but a little bit smaller and crowded
Huawei Ascend P7, enhanced with a 13MP camera and a decent battery lifetime
HTC Desire 816, featuring the same camera type, but lacking a sufficient baterry lifetime
Nexus 5, with a 8MP camera and the latest version of Android and apps