Figures from Strategy Analytics say that 57.3% of all mobiles shipped last year had a removable memory card slot; a total of almost 685 million units. That figure is still growing, with 990 million ‘slotted’ handsets – 68.5% of all phones - expected to have expandable memories by 2013. The new report from Strategy Analytics also says the microSD format is the most popular choice; 71% of last year’s slotted phones used microSD, with the higher-capacity microSDHC format expected to be this year’s preference. [Press release via BusinessWire]