Never leave something behind again! SpaceElephant remembers the space youre in and alerts you when youve left that space. Just click "Remember this Space" and SpaceElephant takes care of the rest!
If you would like to change the defaults, you can set the "Radius in feet" to describe the area you want to remember and/or set the "Alert" to a message that will remind you what you want to remember. Then click "Remember this Space"!
SpaceElephants precision in determining your location can vary depending on your device and the circumstances you are in. For these reasons, you may be able to set the "Radius in feet" setting very precisely in some situations (especially outdoors) but have to set it very loosely in other situations (sometimes indoors). With a small bit of experimentation you can easily discover what works best with your iPhone and your usual situations.
Geolocation is very precise in ideal conditions but can vary greatly in less-than-ideal conditions. According to Apple, "Depending on your device and available services, Location Services uses a combination of cellular, Wi-Fi, Bluetooth, and GPS to determine your location. If youre not within a clear line of sight to GPS satellites, your device can determine your location using crowd-sourced Wi-Fi and cell tower locations or other devices. The accuracy can vary and changed based on moment to moment signal strength and signal availability." See https://www.apple.com/legal/privacy/data/en/location-services/ for more information about GPS, Geolocation, and Location Services.