Steemfollower
Since a few days I'm using Steemfollower and I have to say it is really working.
You don't get ton of upvotes, but definitely more than before.
I almost got no upvotes on my first posts, but after I was using Steemfollower my upvotes got more.
I'm really surprised.
Here is a link if you want to test it out by yourself : https://steemfollower.com/?r=11475
Shadowbot
I also found another side which is usefull too to get some extra Steem.
Shadowbot is a side that automatically votes good contet up and you get some profit from your upvotes.
Here is the link : https://shadowbot.us