You don't need to use IFTTT for this. It is adding complexity, another potential failure mode, and the necessity of Cloud. None of which is beneficial. Just use this...
And suggest search for the subject of presence to find the best way to build a composite/combined presence sensor that will never let you down.
(by the way, thankfully the app works with anything connected to your WiFi router and that has an IP address, best reserved/fixed. So the first thing I did was remove the annoying reference to iPhone 
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