The online map data is hosted by Apple using their CloudKit feature introduced in iOS 8.0. The bandwidth and usage of CloudKit will need to be managed so as not to exceed Apple's quotas. This is the reason for the rolling release. Apple gives a larger quota as more people use the data service so the first two apps will be Grand Canyon and You Need A Map which have a very large number of users with relatively few who have the in-app purchase. The rest of the Scenic Map apps will be next as Apple approves them.
There is one more thing: A new app named simply "Scenic Map". Scenic Map only uses the online maps so the download is small, quick and easy. Scenic Map is free and will be supported by iAds. There is an in-app purchase that upgrades all the features to match those of the other Scenic Map apps and also disables the iAds.
About iAds: There is now an option in the Settings which allows iAds to be turned on in any of the Scenic Map apps. It is off by default but if you want to support Scenic Map or are curious about iAds, feel free to turn it on and off as you wish. iAds are disabled and hidden when there is no connection to Apple's servers. This means that if you don't have a cellular data connection or have cellular data disabled there are no ads. I am encouraging Apple to make better use of the iAd bar to present useful information in addition to ads in future versions of iOS.
Other new features of Scenic Map 1.7:
- Updated maps with more features, most notably woods and forests are visible in many areas as in the screenshot above.
- Multiple track display. You can display one track and when you display a second track the first is no longer hidden automatically. You can display as many tracks as you wish.
- Nautical distance and speed units (requested by airline pilots).
- Support for iOS8 and iPhone 6 and iPhone 6 Plus.
- Seamless worldwide 3D topography maps based on the recently released 30 meter Shuttle Radar Topography Mission data.
- The Online Maps option is off by default in Scenic Map apps. It is on by default for Grand Canyon and You Need A Map when you buy or restore the in-app purchase.
- The Cities Locations search defaults to North America cities. Tap the folder icon in the toolbar and select the area of the world and population size you are looking for.
- Online Maps indicates that data is being loaded with the spinner in the top left corner of the status bar. When the spinner stops, the map is fully loaded.
- The first time the Online Maps is turned on, it may not redraw the screen after the map has been fully loaded. Just use the zoom in and zoom out icons to force the map to redraw. This bug will be fixed in a minor update and should only occur once.
- Up to 2GB of online maps are cached automatically. This size will likely become a user option in a future version however even 2GB is enough to cover a huge area of the world.
- Scrolling adds all visible parts of the map to the download requests. The parts of the map closest to the center of the screen are loaded first.
- Zooming using the + and - buttons in the toolbar resets the map requests. If you want faster map loading, try zooming in.
- Don't try caching the map by zooming all the way out. That only loads the low resolution thumbnails. For best detail, cache the map while zoomed in.