I am playing on an iPhone SE which is basically the iPhone 6 technology. Before 1.2.0, my phone was able to play Minecraft extremely well with a render distance of 14. With 1.2.0 now, I'm locked in at a render distance of 6 which makes it feel like I'm playing Minecraft on an iPod. The render distance is so small that I can't even see my entire Pixel Art builds anymore. This means until I can get bigger render distance back, I cannot do large builds anymore as I will not be able to see the whole thing.

EDIT: Sorry I just saw the other reports for this bug. For everyone who sees this report, restart your device to fix this bug. Hold the Power button and Home button at the same time until your device resets. It worked for me and you can thank the people who found this fix in the other bug reports! If it doesn't sorry but you going to have to wait until a bug fix comes around.