<div>There some options:</div><ul><li>You need to jailbreak and install BTStack.</li></ul>
<div style="text-align: center;">BTStack</div>
<ul><li>Your external device must acomplish MFI Program and you can use External API and
Tips for external.</li></ul><div style="text-align: center;">MFI Terms</div><div>
<ul><li>The iPhone 4S also supports communication with Bluetooth 4.0 Low Power devices through the new Core Bluetooth framework. These devices need not be in the MFi program for you to send and receive data from them within an iOS application. I assume future iOS devices will support this means of communcation, as well. (source) </li></ul> <ul><li> There are other option with low energy consumption bluetooth device. Apple says that if you use a device with this feature you don’t have to use MFI licence</li></ul><div style="text-align: left;">
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</div><div>This is only expectations, I’ve never test it.</div>
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