There’s always a new typographic discovery to be made in London. The city layout was never consciously designed, and many of the streets still follow their pre-Roman line, or wander unpredictably from bend to bend. In the same way, there are a wealth of historical, little-known or unusual letters preserved on our walls or on shopfronts, and it’s a delight to discover them.

Shoreditch-based branding and design agency OPX have now produced a smartphone app LDNTypo for London-based type enthusiasts. It is available for iPhone, with an app for Google Android in the pipeline. If you see a beautiful or unusual example of typography when you’re out in the capital, just take a picture and it will be added to the London Typographica map.

What will eventually emerge will be a massive yet easily navigable database cataloging and preserving the vast range of letterforms to be found on our streets. Many may be lost in the future as people tear down and standardize, but a host of new and extraordinary forms will surely take their place. This is a wonderful enterprise, and will allow all one’s passing snapshots of letters to serve a social and scholarly purpose.