PreferMyFi 2 Lets You Specify Your Preferred WiFi Network on iPhone [Jailbreak Tweak]<img style="float: left; margin-right: 10px"  src="

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If you there are multiple WiFi networks at your home, workplace or any other place, your device will choose a random network and connect to it. In such a situation, you may prefer one WiFi network over the other and there’s no way that you can designate this. Your iPhone will randomly connect to a known WiFi network as soon as you get close in its proximity.   
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PreferMyFi 2 Lets You Specify Your Preferred WiFi Network on iPhone [Jailbreak Tweak]