[kyrra]

Side projects that aren't a conflict of interest when working at Google is rather limiting. Likely less so for small companies.

[yalok]

Not really, in my personal experience and per my friends, most of big companies are pretty lenient about it, except for Apple.

[saagarjha]

No, they're pretty strict. It just changes what you are allowed to do, with Apple being very restrictive in not letting you do it at all.