Hi Konka, in my view the important question here would be how do you define real time updates because you'll always need to consider the network latency, the SDK configuration i.e. whether the values are cached or not if SDK is configured for duty cycle or not, not to mention the very basic speed of light
So if you have a use case where you want to fire an event almost instantly in that case you'd want to have your event firing code as close to the device as possible. But if you have a use case where you just expect values to be updated in Mashup as fast as possible you can use what Ankit has mentioned or via the auto refresh widget on the mashup. Though if you are refreshing every few seconds and if Mashup contains loads of widget which need to be updated you're likely to be observing performance issues with it.