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Yea but sometimes it doesnt work

Always works for me.
You gotta make sure the device you're trying to track has some sort of data connection. Either carrier 3G/2G or connected to wifi.
Also if it cant lock GPS signal it will give you a general blue circle with the area its located. Sometimes if in basements or buildings it wont lock satellite signal.
 
I use cylay and have never had any issue so give that a try if your having issue with the apple one
 
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