i think the idea itself is not essentially bad, the fatal flaw is battery life, ive mentioned this before but ill take the example of the audio add on. as a bit of an audio nerd the idea of good sound from a phone was appealing in a way, but back when i had my note 2 which ran a wolfson dac and didnt sound half bad i had a habit of draining my battery pretty quickly and that was with lower end headphones and mp3s.

now if you were going to shell out and buy the modular add on then chances are youre the sort of person who is also into your music and listens to a reasonable amount on decent headphones with lossless files eating your battery alive. as far as im aware the add on comes with some level of extended battery but the DAC in the modular add on is of higher quality than the wolfson that was in the note i mentioned earlier, for that i have a few extra comparisons.

before i moved to using a stand alone player i did something not that dissimilar to what the LG audio mod does, i connected a good quality portable USB DAC to my phone via OTG, the results were excellent, the sound quality was impeccable but at a hefty price, even the short 45 min bus ride to work could eat over 30% of my battery.

but that was an old phone and not really designed to be running external accessories, so for further comparison ill move on to my separate player, a FiiO X5ii, a device made for one purpose, playing music. while not as tall it is thicker and heavier than just about any smartphone out there and has no touch screen, this (incredible) device will pump out around 10 continuous hours of music, just enough to get through a full working day including commute, so to put it simply pumping out decent quality audio sucks quite a lot of juice. (another more "smartphoney" comparison is my old ibasso DX90, an android based audiophile player with a small touchscreen which used the galaxy S3 battery, even with a 3rd party mugenpower extended battery it only ran for around 7 hours)

so even with any extended battery offered by the add on using it is going to seriously drain your devices life and few of us want to be without our beloved devices meaning youll end up rationing your use of it eventually forgetting about it altogether.

this doesnt just apply to the audio mod either, if you are the kind of person willing to drop a decent chunk of extra cash on upgraded functionality then youre probably the kind of person who uses that feature enough to make using the module a problem for battery life, meaning youre probably better off spending the money on a dedicated device for the job.

once battery tech finally evolves to the point that we can have high level tech from other devices integrated into a single one ill probably be all for the idea but right now my phone can barely handle a day doing what it does already, once that is a little better then we can start thinking of bringing in really high grade tech.

CPU and other component refinements etc are one thing but they can only go so far and were getting pretty near that limit now, we NEED some sort of power breakthrough, whether that comes in the form of a better battery or a better wireless power system is yet to be seen but it needs to happen before truly convergent devices can really progress much further.