"Download Booster" that uses 4g and wifi simultaneously

Hey everybody. I'm thinking of buying this tablet but I first want to know if it can use wifi and 4g at the same time, like the Download Booster feature on recent Samsung phones. This is a big deal for me as my internet connection is very poor (wifi signal is fine so things stay connected but won't load) and I want to smooth things out by using a 4g SIM. I know that I could switch between wifi and 4g when the pages aren't loading, but I want it to happen seamlessly. Thanks