Privacy · Plain-English answer
Many free VPNs collect browsing activity, device identifiers, and location data, then monetise it through advertising partners or data brokers, since the users are the product. Some inject adverts or sell your bandwidth. Not all free tiers are bad, but you should always check how a free service pays its bills.
Running VPN servers costs real money for bandwidth and infrastructure. A free service must cover that somehow. The problematic models include logging and selling browsing data to advertisers or brokers, injecting adverts and trackers into your sessions, and silently reselling your device's bandwidth with no consent. Researchers and regulators have documented free VPN apps doing all three, sometimes while advertising privacy on the same page.
That is the opposite of what a VPN is for. You route all your traffic through the one party best positioned to watch it.
The honest free model is a limited tier funded by paying subscribers, where the free version exists to let you try the service. Signs of that model include a clear privacy policy stating no activity logging, an obvious paid upgrade path, and no requirement to hand over more data than an email.
ROOT VPN follows that model, with one difference it is upfront about. The free tier needs no card, and activity is never logged on any tier. ROOT is funded by paid Plus and Pro plans, plus an opt-in, off-by-default bandwidth-sharing program that is fully disclosed in its own Bandwidth Sharing Terms and routed through ROOT's own servers. Whatever service you pick, read how it earns before you trust it.
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