Invariably when I give a presentation in a new room or conference center the resolution is all different and I cannot see my speaker notes in a consistent way on my laptop, or the screen the audience sees is out of view from me, or some other issue. I would love to be able to sync the speaker notes on my tablet for the presentation I am showing with a mirrored screen on my laptop. (Laptop mirroring the projector, tablet showing the speaker notes)
If you are presenting using a screen or projector with an HDMI port, it is possible to view your speaker notes on your tablet while presenting using the big screen by using the Google Slides mobile app in conjunction with a Chromecast. You could alternately cast the presentation using your laptop for a similar experience.
If you have an Android tablet but do not have a Chromecast and/or the ability to connect to one, you can also use Google Hangouts to present with speaker notes that only display on your tablet. Again, in the Slides app on your tablet, tap the "Present" button; if you have the Hangouts app installed, it will give you the option to present to a new or existing call. On the computer connected to the screen/projector, connect to the same call. (You may need to be logged into Gmail/Google+ as someone else so that you can invite the user of the presentation device to join the call.)
Check out this Google Help Center article for additional information about presenting Google Slides presentations using Chromecast or Hangouts (or AirPlay) and in general.