I heard about Celcius. It does have a good concept and it was even ranked #3 best blockchain project of 2018 by Forbes. Team is also skilled and their CEO is one of the guys involves in invention of VOIP. The only thing is that whenever you transfer your funds for staking on third party platforms then there is always a risk of losing them. Mostly coz of ill-intention projects but sometimes also of lack of security measures or other stupid mistakes. Plus fund management companies like Celcius are always on target of high profile hackers. But ya, if you have loads of stuff lying around, and you just wanna see it grow passively then you can invest small part of it in such projects. Only thing is not everyone has such luxury!
for sure, i'm not sure if this is staking though, i am intrigued indeed- seems HiHi! updated their Telegram saying the Crypto is locked so not like Celsius who seemingly use it.
will dig deeper with the HiHi! site to see exactly how it works as the information is quite scant at the moment, might join their Telegram! seems they have a real team, doesn't look like they are live yet, site looks more like holding/investor site. 
