Mobile or portable apparatus for preparing beverages comprising a module for delivering a beverage by supplying a pressurized liquid, a liquid feed tank of sufficient capacity for supplying the module with several volumes of liquid for supplying more than one beverage, gas pressurizing means suitable for supplying the module with pressurized liquid, a liquid feed chamber, of which the capacity is several times smaller than the capacity of the tank, said chamber being arranged, in a module feeding configuration, to communicate with the gas pressurizing means in order to pressurize the liquid in the chamber and to inject pressurized liquid into the module and thereby permit the delivery of the liquid through the module.