Twelve gigabytes is the new starting line

Of the eighty-odd phones launched at home and overseas in the past quarter, six in ten start at 12GB of working memory. A year ago fewer than two in ten did. A report published this week by a market-research firm puts the shift down to one thing: more and more assistants no longer lean on the cloud but run on the phone itself.

"If the assistant is to answer the moment it is called, the model has to stay in memory," says the analyst who wrote the report. "It cannot slip into the background like an ordinary app and wait for the system to reclaim it."

Where the gigabytes go

By the report's reckoning, a language model compressed enough to run on a phone occupies 3GB to 5GB for as long as it is resident; switch on image generation as well and the peak rises by about 2GB more.

That explains something buyers have noticed: within one range, the feature list of the 8GB model is often two or three lines shorter than that of the 12GB model, and call summaries and offline translation appear only on the larger one.

What the engineers are saving

More memory is not free. An engineer in charge of system optimisation at one phone maker says every extra 4GB adds 3 to 5 per cent to standby power consumption, and a good deal to the cost of the handset. His team has done three things this year: compressed the model once more, loaded it in blocks according to the task, and let the assistant and the camera share part of a cache. "The aim is a model that shrinks when it is idle and is back within half a second when it is wanted," he says. Its resident footprint has fallen by about 30 per cent.

The analyst's advice to anyone about to change phones is direct. If you mean to keep a handset for three years and care about smart features that work offline, 12GB is the safer place to start; for video and chat, 8GB is still enough.

The report expects the average new phone to carry more than 14GB a year from now. By then the contest may have moved from how large a model will fit to how frugally the same memory can run it.