Do most Android device use GPT as their partitioning scheme?
If i'm not wrong, GPT is pretty common. Its pretty advanced format than MBR. On my Kitkat they have 36 partitions. GPT have features like backup partition table and naming/flag, supports larger disk than MBR. (edit:Android 6.0 introduces the ability to adopt external storage media which uses GPT as default partition format.)

Device may or may be aware of GPT.  Typically with MBR first 512 bytes is used for partition table. When we use GPT , it doesn't store any data on 1st sector. Instead marks as  it protective MBR. So that if device looking for MBR complains there is not partition. 

If you interested in in-depth document: 


GUID Partition Table | wikipedia.org
GPT fdisk Tutorial | Rod Smith's Blog