There&#x27;s a lot more activity around intercepting output from sensor-transmitter combos like Dexcom and building a better receiver, or looping the data into a pump. Take a look at this, for example: <a href="http:&#x2F;&#x2F;www.nightscout.info&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.nightscout.info&#x2F;</a><p>A DIY sensor needs to either be some kind of test strip or a needle. Both are a lot easier to just get through insurance than to mimic.<p>I&#x27;m sure you could perform the chemical reactions yourself, but you&#x27;ll probably find whatever you make will need to be replaced frequently. Meanwhile, the software, modified Android phones, etc. last a long longer, so that&#x27;s where is the action.