Currently my system is the following: MKR1000 + laptop with local Blynk server + Android phone + WiFi network from my building.
This configuration allows me to:
log the data sent by the MKR1000 on the laptop even if the App phone is not running. I plan later on to retrieve this data either with the History widget or the web API.
increase the data flow compared to the cloud
keeping the data locally (higher security / confidentiality).
My problem is that this system currently depends on the used WiFi network therefore if I want to demonstrate it elsewhere I have to update the firmware, IP addresses and perhaps even token which is not practical at all.
I was looking into setting an ad-hoc WiFi on the laptop server on which I could connect the phone and the MKR1000 but it turns out Android cannot connect to ad-hoc networks (well known issue after a quick Google search). I’ve anyway tried and I confirm that the network is not seen by Android (even if I enter myself the SSID).
I found on the forum this topic where attempts to use another phone as local server are tested, but apparently unsuccessfully.
Does someone has an idea? Or I’ve reached the limit of this configuration and going back to the Blynk Cloud is the only way out?
Honestly, the issue is your building WiFi. You could easily setup your Local Server on something like RPi with internet access, but you would need to be able to configure port forwarding, thus either working with the building WiFi administrator, or getting private internet (which is best for higher security / confidentiality anyhow). Then your app could connect to the server (which stays home) from anywhere your phone can get internet (and I am assuming your MKR1000 stays home, hooked up to something as well).
Depending on what is being demonstrated then, Blynk’s Bluetooth / BLE option might also work as is offers a serverless link between App and Device. But it is still in Beta and there are many widgets that are not supported.
I have an additional question: is the following system possible at all with Blynk?
Sensor (Arduino or RPi) sending data to the phone e.g. by Bluetooth, in an environment without WiFi
Whenever an internet connection is available, the phone sends the real-time data + if possible, the previously stored data to the Blynk server.
I highly doubt it but I would like to get a confirmation.
I think the sensor has to be connected by GSM/3G to Blynk as well as the phone.
The developers will have tell us if there is anything more than what we already have, with the existing BT/BLE.
As for what works, or is at least available to try, is most everything in the Controllers, Displays, Interface and SmartPhone Sensors with the exception of History Graph and nothing from Notifications or Other, except for Music Player.
Also, I use Android… I am a bit unsure about Blynk’s BLE functionality with IOS.
Your best bet is to start experimenting with it, as I have… remember though, it is still BETA and has quirks.