We gave a lot of thought to this, but a 4k camera adds significant cost (not just for the camera, but the whole computer architecture needs to be replaced because of the intense quantity of data). Plus, the integration effort pushes back delivery several months. Lastly, the 4k sensors have smaller pixels and can’t do as good a job in low-light and with fast moving objects.
We’s focussing on providing a great user experience, and we feel that users prefer the simplicity of HD to 4k. It can be a struggle to find affordable memory cards that can handle the extra data, so why complicate lives when 1080p already gives great quality?
But don’t take our word for it, check out our Kickstarter video. 100% of the aerial shots were done with our LVL 1 drones recording at 1080p.
TLDR; Apple got it right. Bigger pixels are how you get that awesome crisp shot, more pixels is just for marketing.