As mentioned earlier, you should reuse the label textures. 100, 200, 300 textures, all UNIQUE, will consume an incredible amount of framebuffer memory. Your test works on your windows box because your video card has a gigabyte of DDR5 RAM on it. The little mobile notebook won’t have that much memory, and the mobile tablet/phone devices will have even less.
Each label has its own unique texture, which is different than how a loaded texture works. There is no caching of label textures or automatic reuse of said label textures. Reuse them smartly because they are very expensive, especially if they are large 72 point labels.