How cloud VPN ad blockers work
The remote model tunnels your entire connection to a provider's server, where ad domains are stripped and the rest is forwarded. It works — but it means every packet, including logins, banking sessions and personal messages, transits infrastructure the provider controls. Even with honest zero-log policies, the capability exists, and you are trading one observer (ad networks) for another (a VPN operator) plus a new breach surface.
How on-device filtering works
The local model uses Android's VpnService to create a loopback adapter on your phone. DNS queries are matched in device memory against the rule set, ad and tracker domains are sinkholed, and everything else flows directly from your apps to its destination — the phone's normal connection, unproxied. There is no remote hop because there is no remote anything.
| Dimension | On-device (NULLOG) | Cloud VPN blocker |
|---|---|---|
| Who sees your traffic | Only your phone | Provider's servers |
| Log capability | None — filtering in RAM | Technically possible server-side |
| Added latency | Under 0.4 ms local | +50–150 ms server hop |
| Battery cost | Under 1% daily | High — constant encryption overhead |
| Trust model | Zero continuous trust | Trust the operator forever |
When is a cloud VPN the right tool?
Remote VPNs are the right tool for their actual job: changing your apparent location, or hiding your IP from destinations. For ad and tracker blocking they are overkill — you do not need your bank login relayed through Amsterdam to stop a banner from loading. Choosing a tool that matches the job is a privacy decision in itself: the least-privileged architecture wins.
The verdict for ad blocking
For blocking ads, SDKs and telemetry on Android, on-device wins every axis that matters: no visibility into your traffic, no log capability, no latency penalty, no battery tax. It is also the only architecture whose privacy claim you can verify — if nothing leaves the device, there is nothing to subpoena, breach or quietly repurpose.
Put it into practice with NULLOG
NULLOG runs every technique in this guide locally on your Android — ads, trackers and telemetry filtered in device memory. No root. No cloud. No logs.
Download NULLOG APK (v1.0.2)