I’m unable to offer you any advice in context of an App - but consider this...
WiFi Only models of iPad do not have any GPS capabilities. WiFi Only models of iPad are entirely reliant upon their WiFi network for location services to work - and in so doing, their ability to estimate their location is limited. The location is derived from an external database lookup of adjacent WiFi networks.
As such, any reported location of WiFi Only models of iPad will be limited to the derived location of the WiFi Network to which the iPads are connected. This method of deriving the network location is reasonably accurate in urban and metropolitan areas - but is unreliable, if it works at all, in rural or sparsely populated areas that have few adjacent WiFi networks.
WiFi & Cellular models of iPad do include GPS positioning - as this functionality is integral to the Cellular chipset.