A drinkware container system, comprising: a container (5000; 6900; 7300) having a chamber (5015; 6950; 7315) that receives and holds a liquid, one or more heating or cooling elements (5040; 6940; 7340) incorporated into the container (5000; 6900; 7300) in thermal communication with the liquid in the chamber (5015; 6950; 7315), and one or more electrical contacts via which power is provided to the one or more heating or cooling elements (5040; 6940; 7340) and to one or more sensors in the container (5000; 6900; 7300); and a module (6990; 7390) removably coupleable to a bottom portion of the container (5000; 6900; 7300), the module (6990; 7390) having, one or more electrical contacts that contact the one or more electrical contacts of the container (5000; 6900; 7300), one or more power storage elements (5060; 6260; 7360), and control circuitry (5080; 6280; 7380), wherein when the module (6990; 7390) is attached to the container (5000; 6900; 7300), the control circuitry (5080; 6280; 7380) can control the operation of the one or more heating or cooling elements (5040; 6940; 7340) to maintain or increase the temperature of the liquid based at least in part on information from the one or more sensors that sense a parameter of the liquid; the drinkware container system characterised in that the module (6990; 7390) is configured to be removably coupleable to the bottom portion of the container (5000; 6900; 7300) solely via one or more magnets (6992; 7392) in the module (6990; 7390), the one or more magnets (6992; 7392) being configured to magnetically couple the module (6990; 7390) to the container (5000; 6900; 7300) such that a user can couple the container (5000; 6900; 7300) to the module (6990; 7390) with one hand. a container (5000; 6900; 7300) having a chamber (5015; 6950; 7315) that receives and holds a liquid, one or more heating or cooling elements (5040; 6940; 7340) incorporated into the container (5000; 6900; 7300) in thermal communication with the liquid in the chamber (5015; 6950; 7315), and one or more electrical contacts via which power is provided to the one or more heating or cooling elements (5040; 6940; 7340) and to one or more sensors in the container (5000; 6900; 7300); and a module (6990; 7390) removably coupleable to a bottom portion of the container (5000; 6900; 7300), the module (6990; 7390) having, one or more electrical contacts that contact the one or more electrical contacts of the container (5000; 6900; 7300), one or more power storage elements (5060; 6260; 7360), and control circuitry (5080; 6280; 7380), one or more electrical contacts that contact the one or more electrical contacts of the container (5000; 6900; 7300), one or more power storage elements (5060; 6260; 7360), and control circuitry (5080; 6280; 7380), wherein when the module (6990; 7390) is attached to the container (5000; 6900; 7300), the control circuitry (5080; 6280; 7380) can control the operation of the one or more heating or cooling elements (5040; 6940; 7340) to maintain or increase the temperature of the liquid based at least in part on information from the one or more sensors that sense a parameter of the liquid; the drinkware container system characterised in that the module (6990; 7390) is configured to be removably coupleable to the bottom portion of the container (5000; 6900; 7300) solely via one or more magnets (6992; 7392) in the module (6990; 7390), the one or more magnets (6992; 7392) being configured to magnetically couple the module (6990; 7390) to the container (5000; 6900; 7300) such that a user can couple the container (5000; 6900; 7300) to the module (6990; 7390) with one hand. <EOS>