The Geonotes app is built on the Geoloqi API and is an extension of the Geoloqi demo app, taking advantage of the battery and accuracy improvements in the new SDK (software development kit). The app also provides users with access to free geo layers that the folks at Geoloqi spend their time making.
The Google Maps API team maintains many Google Maps APIs and SDKs. Manually tracking updates across the various sets of Release Notes presents a challenge for developers. Google now offers auto-updates to Maps Release Notes via RSS feeds. RSS feeds for all Maps and Places APIs are available.