One of my first attempts at productivity using tech hacks was the Call app. This was during the early days of Startup Village and around when my call volumes started increasing manifold. Receiving 2 to 3 in call waiting by the time I was done with a call was turning out to be a regular occurrence.
It was at this point that I attempted to try out an approach and got Zach to build me a custom mobile app for that. The app would cut the call automatically if not picked up within 3 rings and send a text to the caller. Not able to recall the exact body of text but it went something like this.
Appears that I am unavailable now
Text me what its about so that I may get back / facilitate / call back.
Shifting to this approach came with its share of hiccups and resistance from some quarters. Beyond that it started working well for me overall. For every 10 calls, I observed that I needed to call back in only 2 to 3 instances. Rest of the time, a brief text message would have sufficed saving the need for a call.