Using your own cloud server, host a location reporting service. Share your mobile location with friends and view their location. Source available for both client and server pieces.
This app requires the UserHash servlet (userhash.war, link below) to run at the "userhash server url" in the app settings.
It is convenient to run nginx as the front facing web server proxying requests to tomcat in the background.
For example if you have a small 512k VPS with a Ubuntu image, you can install the following:
apt-get install nginx
apt-get install tomcat7
apt-get install default-jdk
For SSL support (recommended), install a self-signed cert in nginx
and add users/passwords in /etc/nginx/htpassword
The file nginx-site contains sample settings for nginx with SSL.
Also modify the tomcat's server.xml to add address="127.0.0.1", localhost only.
In the app in Settings, you can paste your self signed cert if you want to use one.
The list of users on your userhash server to view and will also be the ones you share your location with.
Currently if you change the update minutes, you have to restart your phone to take effect.
Apache license, source at: