For buyers contracting authority
Pick 48326100 when the deliverable is a working mapping or GIS software system: a platform that holds geospatial layers and lets staff query, edit, and display them. Departmental GIS rollouts, cartography tools, and land or asset systems built on a spatial database belong here.
The boundary that trips contracting authorities is the parent 48326000. Use the parent when the scope is mapping software in general and no single product dominates; reserve 48326100 for the digital mapping system as the named, deliverable platform. One step out, if the contract is mainly a survey, an aerial-imagery acquisition, or a data-capture exercise rather than the software that holds the result, the mapping-software family is the wrong home.
Watch the build-versus-product line too. Where an authority commissions a bespoke geographic application written for it, a custom software-development code can fit better than this product-shaped one. Set the primary CPV code by the dominant purpose: a mapping software system points here, a coding engagement points to development.