title: Android : Get notification when user enter in specific location
body: <p>I am developing android application which gives notification when user enter in specific location <br/>
  User can specify the location by using latitude longitude(ie Google Map)<br/>
  I know how to get latitude &amp; longitude but my problem is that when user enter in specific location then it will not exactly match with previously specified latitude &amp; longitude.
  <img src="https://i.stack.imgur.com/rVl7Y.jpg" alt="enter image description here"></p>
  
  <p>As shown in image suppose user specify the location called "My Place" when user enter in area (about 20 meter) then application should send notification to user.<br/>
  <strong>I want know how I can compare the latitude &amp; longitude which user specified(My place) and current latitude &amp; longitude which application fetch by GPS.</strong>
  The comparison made in such way that it will true if user near by of My place in area of 20 meter.
  (This 20 meters is approximate.)
  Can I set accuracy of in android e.g. 20 meters.<br/>
  Thank you.</p>