Lightning Network is much much closer to going live now. That would be a federated (email&#x2F;XMPP like) system to drastically boost the number of transactions per second that it can handle with retained security (a malicious LN server can at worst temporarily freeze funds and reverse only unsettled payments).<p>You don&#x27;t need to trust third parties even with mobile devices, the Bitcoin Wallet app on Android uses the SPV protocol where a malicious miner has to outpace the rest of the miners to fool you. It uses the code library bitcoinj. Headers-first sync only made this easier to do with minimal resources.