I was checking Bitrefill twitter until I saw they tweet regarding a service called
Afterburner which is made by Samourai wallet. The service can be used by downloading their app from
Google play, downloading is free but boosting your transaction isn't.
"
To unstuck a transaction you will be charged $5.99 in BTC plus the fee required to the bitcoin miners which varies based on network conditions and transaction size"
I haven't used the service myself so that's why I'm asking here on the first place, the wallet will only work with HD wallets and will ask you for your passphrase, that made me a little bit worried but in the same time, the project is open source so I just wanna know If someone already used this and could tell us how reliable this app is.