I recommended this App back in Nov ’14: It’s great for viewing eg Victoria’s Topo maps in a Georeferenced form, ie the GPS on your phone will work to show your location, route etc on the map. All Qld’s Topo maps will also work and are available free here: http://qtopo.dnrm.qld.gov.au/mobile/.
Many folks have probably noticed that their Pdf Maps App has updated to Avenza and that now they are only able to open three maps for free instead of an unlimited number of maps, and that Avenza would like them to pay over $30 per year to restore the functionality they had before!
As I understand it, Pdf Maps (version 1.7.3) is free software – indeed it seems that its functionality may well have been created by someone else ie TerraGo – see this Wikipedia article: https://en.wikipedia.org/wiki/Geospatial_PDF. In any case you can download it for free from a variety of sources, eg http://pdf-maps.en.uptodown.com/android/download or https://allfreeapk.com/avenza-maps,407396/
You simply uninstall the Avenza App and install the Pdf Maps App which you have downloaded. (I have downloaded a copy from the first of these and Norton declares it virus free – and it certainly works). I think because the App did not come from Google’s Play Store it will not appear in Play Store’s list of your Apps and Games so it will probably not update automatically (at all), and should continue to function indefinitely.
However, this Youtube https://www.youtube.com/watch?v=fMFQupwDNhU&spfreload=10 (and others https://www.youtube.com/watch?v=IdkWwT8YKNg) tells you how to uninstall Avenza and put Pdf Maps in its place. He says among other things, you have to be sure to cancel the ‘Update’ function so this doesn’t happen to you again. Important: What you have to do is straight after you have installed the App but before you open it click on the three dots on the top right hand corner of the screen. This will give you the option to dis-enable auto update of the App..
Once again you will be able to open an unlimited number of Pdf maps for free – such as can be bought from: http://services.land.vic.gov.au/maps/imf/search/Topo30Front.jsp some of which you may need to walk The Upper Yarra Track, for example: http://finnsheep.com/THE%20UPPER%20YARRA%20WALKING%20TRACK.htm
Or, if a friend has already bought a copy of one or more of these Vicmaps they will be able to share them with you.