Campaigners against Israeli settlements in the occupied Palestinian territories have launched a new web and iPhone application that uses powerful mapping technologies to publicise data that was previously hidden away, inaccessible, or simply too costly to distribute.

American Friends of Peace Now (APN), a Washington-based group, says its Facts On the Ground app will allow anyone, anywhere, to access comprehensive, real-time information about Israeli settlements and to learn what is happening on the ground in the West Bank and East Jerusalem.

The launch comes as diplomatic pressure intensified on Israel to renew a partial moratorium on settlement-building that is due to expire this weekend. Israel has repeatedly insisted it will not renew it while Palestinians have threatened to walk out of the recently revived US-brokered peace negotiations if it does not.

Information about settlements is notoriously hard to collate and analyse because Israel makes a distinction between the West Bank and East Jerusalem – though both are occupied territory under international law – and because different government departments and other agencies can approve construction. Building and sales are private-sector activities.

Supporters of settlements are poised to initiate a wave of new building work the moment the moratorium deadline expires on Saturday. In the past, settlers have often set up unauthorised outposts and challenged the government to remove them.

"Our app will update constantly to reflect breaking events such as settlement or outpost construction, outpost removals, Palestinian violence or settler violence, making it a real-time tool that provides context to the ever-changing situation in Israel and the West Bank," APN said.

The app allows users to look at different layers and overlays. It uses a Google Earth-type format to display map, satellite, hybrid or terrain images. It divides the West Bank into areas A, B and C under the 1993 Oslo accords, in which the Palestinian Authority and Israelis exercise different levels of control.

It also shows how Israel's West Bank barrier relates to the pre-1967 border, which the Palestinians say must be the basis for a long-term peace settlement. Some 300,000 Israelis live in 120 officially recognised settlements in the West Bank, a further 192,000 in settlements in East Jerusalem, and there are 100 unauthorised outposts in the West Bank that are not officially recognised by Israel.

The app's users can zoom in on dense clusters of settlements around Jerusalem and in Hebron, and single out large-scale maps of individual settlements complete with historical and population data.

The app is available for the iPhone and iPad and will soon be available for Android hand-held devices, APN said. A Hebrew edition will be available within weeks.