I've got a standalone electric smoker, a standalone propane grill, and a charcoal kettle grill.
If I'm smoking, I'm smoking. If I'm grilling, I'm grilling. Each gizmo is very good at what it does, especially considering what little I paid for them.
Smokers are kind of a set-it-and-forget-it thing, at least for an hour or so at a time. You don't want to be opening the door very often as that lets out the heat and extends your cook time considerably. Remote probe thermometers are a thing, and you can get them cheaply, which is good because they do tend to glitch and need replacing. So I wouldn't get a Bluetooth thermometer unless I could easily calibrate it after it starts to get weird.
Portability will be a function of size. I built a stand with casters on my smoker so I can roll it around my patio, and put it away in the winter. It's relatively small, about the size of a dorm fridge, and will smoke 2 turkeys (broken down into quarters, on 3 trays) so about 20-30# of meat. Which, really, is plenty for any family gathering. Something that can double as a grill will be larger and less portable.
Unless you look at those Big Green Egg-ty pe ceramic komodo cookers. They're heavy but do dang near anything that needs to be done in the kitchen, except maybe washing dishes. They burn charcoal. Definitely some technique to these things but the people I know who have them won't shut up about them, so there must be something there.