Imag­ine this: you’re a busy social media man­ag­er with friends scat­tered across a raft of dif­fer­ent social net­works and you’d like to be able to chat pri­vate­ly with all of them from one place with­out the headache of reg­is­ter­ing sep­a­rate accounts on each net­work. Sound like an impos­si­ble day­dream? Not so, accord­ing to the founders of the new cross-plat­form mobile mes­sag­ing app Uni Messenger.

Found­ed in June, the start­up is the brain­child of Colum­bia Com­put­er Sci­ence grad David Hun­ing and Joe Huaqiao Chiu, who’d been devel­op­ing a cross-plat­form social media com­mu­ni­ca­tions solu­tion while based in Chi­na in 2011. The firm now employs almost a dozen part-timers and eight full-timers at its San Fran­cis­co office.

Reach­ing every­one from one app

The new app is due to be launched next month and has been devel­oped for the Android OS (at least to begin with). It will seam­less­ly com­bine all the social net­work­ing con­tacts of its users into a sin­gle easy-to-access address book – yup, that means Twit­ter, Face­book, LinkedIn, Ten­cent Wei­bo, Sina Wei­bo, VK, Mixi and Cyworld (sup­port for Google+ is in the pipeline). OK, so in that respect, it’s not too dis­sim­i­lar from oth­er social address book apps like Addappt, Brew­ster and Cobook. But that’s only the begin­ning for Uni Mes­sen­ger: the next step is to let the user mes­sage all their friends, irre­spec­tive of what social net­work they’re on, straight from the app.

The can­ny social media man­ag­er will almost sure­ly be ask­ing at this point, how? It uses the net­works’ APIs to send mes­sages to con­tacts in their pri­vate inbox­es, whether that’s LinkedIn’s Email or Twitter’s Direct Message.

Ambi­tious but exciting

Vet­er­an social media man­agers may find the prospect just a tad on the “high­ly ambi­tious” end of the spec­trum, and that’s a fair assess­ment. Each network’s API and poli­cies will deter­mine how pos­si­ble it’s going to be – you can send a mes­sage to friend on Face­book, but she’ll need to down­load the Uni Mes­sen­ger app if she wants to read it.

But if it catch­es on and friends all have the app, it includes app fea­tures like group chat (called “Cir­cles on Uni Mes­sen­ger), loca­tion and pho­to shar­ing and sev­er­al more cur­rent­ly under devel­op­ment (like mul­ti-lan­guage sup­port, email, SMS, voice and video calls).

This could go far. And it’ll be a first.