For seeing what people are searching google for. I use it for coins and exchanges.
https://trends.google.com/trends/
For seeing website traffic, like for exchanges, and news sites.
https://www.similarweb.com/
I use this one to see how loaded the blockchains are
http://www.blocktivity.info/
This site has technical info for the Bitcoin blockchain, like fees per transaction, block size, etc.
https://oxt.me/
These ones track social media activity for coins.
https://solume.io/
https://coinmunity.co/
http://www.cryptoparse.io
https://cointrendz.com/
http://altcoinanalytics.com/
Any more?