For most surveys, you do not need to worry about Offline Maps. When on-site, if you have a good/fair connection to the internet then the OTISS survey apps will be able to display the required maps and use them for your surveying. The survey apps will automatically store parts of the maps on the phone/tablet’s SD card to increase performance and reduce 4G/3G data usage – but you don’t have to do anything.
However, for areas of poor 4G/3G mobile signal, you will want to pre-load the maps before you leave your home/office. From the list of Downloaded Surveys, you can select a survey and goto the new Download Maps page.
Read more about the Download Offline Maps feature.