Interacting with an electronic device through physical movement

1. An electronic device, comprising:

a display screen;

a biological sensor;

one or more processors; and

memory storing one or more programs configured to be executed by the one or more processors, the one or more programs including instructions for:

displaying an affordance on the display screen;

receiving biological sensor input associated with a positioning of a user's hand; and

in response to receiving the biological sensor input:

in accordance with a determination that the biological sensor input corresponds to a predefined pattern, the predefined pattern being associated with the positioning of the user's hand, displaying an indication that the biological sensor input corresponds to the predefined pattern before performing an operation associated with the affordance;

in accordance with a determination that the biological sensor input corresponds to the predefined pattern for a predetermined time, performing the operation associated with the affordance; and

in accordance with a determination that the sensor input does not correspond to the predefined pattern for the predetermined time, forgoing performing the operation associated with the affordance.

2. The electronic device of claim 1 , wherein the one or more programs further include instructions for:

in accordance with the determination that the biological sensor input corresponds to the predefined pattern for the predetermined time, modifying a visual appearance of the affordance.

3. The electronic device of claim 1 , wherein the one or more programs further include instructions for:

in accordance with a determination that the biological sensor input corresponds to the predefined pattern, displaying a graphical element indicating the predetermined time.

4. The electronic device of claim 1 , wherein the electronic device further comprises a haptic feedback mechanism, and wherein the one or more programs further include instructions for:

further in accordance with the determination that the biological sensor input corresponds to the predefined pattern, providing a haptic feedback, via the haptic feedback mechanism.

5. The electronic device of claim 1 , wherein the operation comprises answering a telephone call.

6. The electronic device of claim 1 , wherein the biological sensor comprises an optical sensor positioned in the electronic device to measure blood flow indicative of a clenched hand of the user.

7. A method, comprising:

at an electronic device with a display screen and a biological sensor:

displaying an affordance on the display screen;

receiving biological sensor input associated with a positioning of a user's hand; and

in response to receiving the biological sensor input:

in accordance with a determination that the biological sensor input corresponds to a predefined pattern, the predefined pattern being associated with the positioning of the user's hand, displaying an indication that the biological sensor input corresponds to the predefined pattern before performing an operation associated with the affordance;

in accordance with a determination that the biological sensor input corresponds to the predefined pattern for a predetermined time, performing the operation associated with the affordance; and

in accordance with a determination that the sensor input does not correspond to the predefined pattern for the predetermined time, forgoing performing the operation associated with the affordance.

8. The method of claim 7 , further comprising:

in accordance with the determination that the biological sensor input corresponds to the predefined pattern for the predetermined time, modifying a visual appearance of the affordance.

9. The method of claim 7 , further comprising:

in accordance with a determination that the biological sensor input corresponds to the predefined pattern, displaying a graphical element indicating the predetermined time.

10. The method of claim 7 , wherein the electronic device includes a haptic feedback mechanism, the method further comprising:

further in accordance with the determination that the biological sensor input corresponds to the predefined pattern, providing a haptic feedback, via the haptic feedback mechanism.

11. The method of claim 7 , wherein the operation comprises answering a telephone call.

12. The method of claim 7 , wherein the biological sensor comprises an optical sensor positioned in the electronic device to measure blood flow indicative of a clenched hand of the user.

13. A non-transitory computer-readable storage medium storing one or more programs configured to be executed by one or more processors of an electronic device with a display screen and a biological sensor, the one or more programs including instructions for;

displaying an affordance on the display screen;

receiving biological sensor input associated with a positioning of a user's hand; and

in response to receiving the biological sensor input:

in accordance with a determination that the biological sensor input corresponds to a predefined pattern, the predefined pattern being associated with the positioning of the user's hand, displaying an indication that the biological sensor input corresponds to the predefined pattern before performing an operation associated with the affordance;

in accordance with a determination that the biological sensor input corresponds to the predefined pattern for a predetermined time, performing the operation associated with the affordance; and

in accordance with a determination that the sensor input does not correspond to the predefined pattern for the predetermined time, forgoing performing the operation associated with the affordance.

14. The non-transitory computer-readable storage medium of claim 13 , wherein the one or more programs further include instructions for:

in accordance with the determination that the biological sensor input corresponds to the predefined pattern for the predetermined time, modifying a visual appearance of the affordance.

15. The non-transitory computer-readable storage medium of claim 13 , wherein the one or more programs further include instructions for:

in accordance with a determination that the biological sensor input corresponds to the predefined pattern, displaying a graphical element indicating the predetermined time.

16. The non-transitory computer-readable storage medium of claim 13 , wherein the electronic device includes a haptic feedback mechanism, and wherein the one or more programs further include instructions for:

further in accordance with the determination that the biological sensor input corresponds to the predefined pattern, providing a haptic feedback, via the haptic feedback mechanism.

17. The non-transitory computer-readable storage medium of claim 13 , wherein the operation comprises answering a telephone call.

18. The non-transitory computer-readable storage medium of claim 13 , wherein the biological sensor comprises an optical sensor positioned in the electronic device to measure blood flow indicative of a clenched hand of the user.