If you're taking a trip to the UK anytime soon, make sure you've signed up for its new electronic entry form
Briefly

As of January 8, US and Canadian citizens are among 48 nationalities who will need an Electronic Travel Authorization (ETA), which is required for both entry and layovers.
The UK ETA application process is straightforward, taking only about 10 minutes via the mobile app, involving a passport scan and basic personal information.
Read at Business Insider
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