A method for executing an operation in a client device platform, comprising: recording one or more non-tactile inputs to the client device platform with one or more sensors, wherein the one or more inputs are recorded to a first memory, wherein the client device platform is operating in a low-power state in which power is provided to a first processor and the first memory; generating one or more first confidence scores, wherein each of the one or more first confidence scores is a measure of a degree of similarity between a corresponding recorded non-tactile input and a first reference input stored in the first memory; generating a final first confidence score from the one or more first confidence scores, wherein two or more first confidence scores corresponding to different types of non-tactile input are combined to generate the final first confidence score; initiating an intermediate-power state of the client device platform when the final first confidence score is above a first threshold level, wherein the intermediate-power state comprises providing power to at least a second processor wherein the second processor has a greater amount of available processing capability than the first processor; outputting a challenge signal that is detectable to a human when the final first confidence score is within a challenge range between a rejection range and the first threshold level, and initiating the intermediate-power state when a non-tactile response to the challenge signal is detected by one or more of the sensors; generating one or more second confidence scores with the second processor, wherein each of the one or more second confidence scores is a measure of a degree of similarity between each recorded non-tactile input and a second reference input; generating a final second confidence score from the one or more second confidence scores, wherein two or more second confidence scores corresponding to different types of non-tactile input are combined to generate the final second confidence score; generating a command signal that instructs the client device platform to execute one or more operations that are associated with the second reference input when the final second confidence score is above a second threshold level. recording one or more non-tactile inputs to the client device platform with one or more sensors, wherein the one or more inputs are recorded to a first memory, wherein the client device platform is operating in a low-power state in which power is provided to a first processor and the first memory; generating one or more first confidence scores, wherein each of the one or more first confidence scores is a measure of a degree of similarity between a corresponding recorded non-tactile input and a first reference input stored in the first memory; generating a final first confidence score from the one or more first confidence scores, wherein two or more first confidence scores corresponding to different types of non-tactile input are combined to generate the final first confidence score; initiating an intermediate-power state of the client device platform when the final first confidence score is above a first threshold level, wherein the intermediate-power state comprises providing power to at least a second processor wherein the second processor has a greater amount of available processing capability than the first processor; outputting a challenge signal that is detectable to a human when the final first confidence score is within a challenge range between a rejection range and the first threshold level, and initiating the intermediate-power state when a non-tactile response to the challenge signal is detected by one or more of the sensors; generating one or more second confidence scores with the second processor, wherein each of the one or more second confidence scores is a measure of a degree of similarity between each recorded non-tactile input and a second reference input; generating a final second confidence score from the one or more second confidence scores, wherein two or more second confidence scores corresponding to different types of non-tactile input are combined to generate the final second confidence score; generating a command signal that instructs the client device platform to execute one or more operations that are associated with the second reference input when the final second confidence score is above a second threshold level.