Great question - I have worked on several projects relating directly to what you are describing (based on my initial understanding) including providing software interfacing for mobile/PC/TV for large-scale hardware manufacturers as well as for mobile devices connecting to sensors and translating/reading data sent from equipment buried several feet under the ground to track eco changes for contractors. Assuming by device we are referencing mobile/smartphones (and possibly connectivity with hardware on two different platforms?), in which case I would imagine Bluetooth connectivity should be able to get the job done for you. There are really a lot of factors that could go into either how to utilize Bluetooth, or if an alternative path towards connectivity would be required (the device types you're connecting, their congruence/similarity, if there are prompts on the push/pull pinging, where the data from each activity is being housed once completed, geo-relevancy and latency requirements to name a few.) I'd be happy to set aside a few minutes to talk about the details of your project and provide any additional insight I can on how can you connect these devices and build out your system.

Hi — the question needs more context, to see what environment you are trying to have this run on. "Ping" will need some sort of transport network; although it doesn't have to use the Internet or wifi.

Let me know if you want to discuss it further.

I'm an engineer with very extensive experience in hardware prototyping, some of which has led to millions of dollars of investment.

Yes there are many many ways that two electronic devices could communicate with each other without using "wifi or data". Each of these alternatives would have different advantages depending on the situation in which you wish to use the devices (range, ambient light conditions, etc).

If you would like to discuss this give me a call.