Have a look at Canary units - motion detection - records last few hours to secure web site (I think it's 12 hours) and sends alerts to your phone, and you can activate really loud alarm if you get alert - my mate has one and it's cracking bit of kit (£139 from currys)
I dont want to sound like a scaremonger, but I would have to look very hard at any solution that relies on third parties/cloud for any part of its provision. Particularly for a device for which the main function is surveillence.
At the very least it needs to have updatable firmware and not be susceptible to heart bleed and poodle. Often these devices rely on buggy recycled firmware to keep thr costs down.