Decypher
Learn about royal cyphers on post boxes in the UK.
At a glance
Starts at
Free
No paid plan found on the App Store, September 2026.
Free tier
No
Platforms
iPhone
Best for
Curious history enthusiasts, tourists
Not for
History buffs outside uk
3.7 out of 5
Scored by a Toolio reviewer after real useOur verdict
Decypher is a great way to learn street-level history. It's perfect for those walking through London or other UK cities who want to explore their surroundings with an educational lens. However, it focuses narrowly on post boxes and does not offer broader historical context.
✓What it does well
Identifies post box historySpot cyphers and learn about their significance in the UK.
Easy to use interfaceProvides a simple, intuitive way to interact with street furniture.
Works well on older devicesThe app runs smoothly even on iPhones from the XS model onwards.
✕Where it falls short
Limited to UK post boxesDoes not provide information about other types of street furniture or historical sites in general.
No broader contextFocuses solely on identifying and explaining royal cyphers, missing out on a wider historical narrative.
Dependent on good lighting and camera qualityWorks best in well-lit areas with clear images; performance can be inconsistent under poor conditions.
Key features
Camera-based identificationUses your device’s camera to recognize post boxes and their cyphers.
Historical informationProvides background on the history of royal cyphers and local neighborhoods.
User-friendly designOffers an intuitive experience, making it accessible for users to learn about post boxes easily.
extended contentprovides more detailed information