Can i make an app that control relay turning on and off using gprs/internet on gsm sim900a module with arduino uno r3

i dont want to use text message to control or triggering relay on and off becoz sometimes text message recieves very soon.

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buddy simply i am asking to you that is it possible to make an app that control RELAY using gsm and arduino over internet,
becoz the issue is that i dont want to use text message due to netwrok issue sometimes sms not recieved, instead of that i want to use

gprs connectivity to control the relay over the internet via mit app i am attaching some screenshots, in which i am using direct text sms to control relay using text messages

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A few years ago I've used a SIM800C to do the same application as yours (remotely driving relays by means of a SMS). Since sometimes it was not working fine (poor GPRS signal), I've changed the SIM800 with a newer SIM900, but the improvement has been negligible.
Then I've changed the structure of the receiver by removing the SIM900 and putting an old phone in its place. On the old phone, I've loaded an app (written by me using AI2) that receives the incoming SMS and transfers the contents to the Arduino board by means of a BT comm's and it works perfectly since many months without losing any single SMS.


After a lot of research, I understand that the sms sending and recieving process takes minimum 4 seconds and 430 milliseconds to send from the sender to reciever over 4300 milliseconds instead of that
I found another solution for this problem is that i should use google firebase/realtime database over internet, to enable internet using gprs connectivity we have to configure in its arduino program to access internet on sim 900A to connect http server,
And the one more thing to make it to much fast we should use our nearest server database location if
There are three different severs are located in three different regions of globe first one is in america , second one is in europe and the third one is located in singapore south east asia which is the nearest database from my country(india).

Thanks for having shared the results of your research.

Honestly I didn't understand that you were facing transmission speed problems, while I understood that the problem was mainly a poor signal. Therefore my suggestion was to scrap the SIM900 and use a cell phone instead.
In my application I have had also the need to put the cell phone where the signal is good, while the Arduino board is located in the garage, where the cell signal is very poor and unstable. So the phone behaves like an antenna that receives the command SMS, it parses the SMS, and transmits the command via BT to the Arduino board that operates on the actuators and sensors (in the garage).

buddy if we are dealing with hardware components then we need to find the solution in its context, replacing whole hardware components/modules by a cellphone which is not seems as a professional work in my context, because if i am developing a new product for any organization/company then i can't put a cell phone in that device i hope you understand what i am trying to say, instead of cell phone you should learn or find another way such as use wifi in your basement to connect over internet without using any gsm module to google realtime database or firebase.
i will show you later why i bulid the whole system, its program, its application and its hardware components.

Sure, my app was just for personal use, not for business.
I've dealt with embedded SW (aerospace equipment) for 40 years, and now I'm "playing" with Arduino and MIT, so I'm pretty aware about HW concerns. :thinking:
I wish you great success with your product !!!


I tried firebase 4 years ago. I wanted to control lights with it. For me firebase was slow too. Not 4 seconds, only 1 or 2 sec but not fast enough. So better to find a faster cloud server. But if you okay with 1-2 sec late, then no problem. And maybe the firebase server advenced a little in 4 years. Ad maybe there are faster, paid options for firebase too?