Data Geo Localization turns the addresses you already keep on your customers into real map positions, and shows them on a Google map that opens straight from the Customer Card. When you open the map on a customer, you also see every other customer within the distance you choose.
Use it to:
The field and button names below are those shown when the English language is active.
Page: Company Information → Aptagram section
Action: fill in the two fields:
The two fields sit in their own Aptagram group, at the bottom of the page.

Here the radius is set to 50,00, and the key is saved and therefore masked.
What happens: the app can now look up positions and draw the map. Without a key nothing works: opening the map answers Google API key missing, please add it in the company information page.
The key is yours, not Aptagram's: usage and cost of the map and lookups are billed by Google to that key, so keep the usual restrictions on it in the Google console.
The radius is the straight-line distance from the customer you opened the map on — as the crow flies, not the distance driven. A road route is always longer, so a value slightly larger than the distance you have in mind gives the more useful picture.
Leaving Google Maps Max Km Radius at 0 turns the limit off: the map then shows every customer that has a position, wherever it is. That is fine for a handful of customers and unreadable for a few thousand — set a real radius as soon as the map starts to feel crowded.
Page: Customer Card → Customers Map action (also available in the promoted actions at the top of the card)
Action: open the customer you are interested in and choose Customers Map.

What happens: the map opens centred on that customer:
Below, the map was opened on customer Relecloud: it is the red marker, and the other customers around it are blue. Two markers have been clicked, so their name and address are shown.

The map is a normal Google map: you can zoom, pan and switch to satellite view as you would in a browser.
You never type coordinates by hand. The first time a customer's position is needed, the app sends its address to Google and stores the Latitude and Longitude it gets back on the customer, so the lookup is done only once.
The address sent to Google is built from four fields of the customer: Address, City, County and Post Code. City is the one that must be filled in — a customer with an empty City is never positioned, and opening the map on it answers Sorry but we were unable to find the position of customer ….
Page: Customer Card
Action: change the Address, City, County or Post Code of a customer and save.
What happens: the stored position is cleared straight away, and it is looked up again the next time the customer appears on a map. You do not have to remember to refresh anything; the map simply follows the address.
Changing any other field — the name, the phone number, the payment terms — leaves the position untouched, because it does not change where the customer is.