Once you have connected a few lights - say a Hue bulb, a LIFX light and one or two Z-Wave lights then a simple way to group these together is to use the Cubes feature.
1. Create a new Cube: My Lights On.
2. Add the various lights to that Cube - could even include a plug-in such as a Belkin or Z-Wave type that turns a table lamp on/off too.
3. Set the condition you want for each light - doesn't have to be just on, could be a certain colour and/or a certain brightness depending on each light.
4. Decide if that's a Favourite Cube with the star icon at the top right - that places the Cube right in the Cube section of the Dashboard so you can reach it with a single click when opening the nCube app.
Now on the Dashboard, or from the list of Cubes, just press the Play button to instantly use it.
If you're after a way to also turn them off then at the moment the only way is to create a second Cube with the same set of lights and the conditions all set to off. Say call that 'Lights Off'.