Accessibility techniques for presentation of symbolic expressions

One or more non-transitory computer-readable media storing one or more programs which, when executed by a computing device with a touch-sensitive surface and one or more audible output devices, cause the computing device to perform steps comprising:

• determining portions within a symbolic expression, the symbolic expression including at least one portion having a plurality of sub-portions;
• detecting a first tap gesture on the touch-sensitive surface directed to the portion of the symbolic expression, wherein the first contact corresponds to a location-dependent navigation input;
• in response to detecting the first tap gesture, placing a focus on the portion of the symbolic expression and outputting audible information that corresponds to the portion of the symbolic expression;
• detecting a first flick gesture outside of the symbolic expression on the touch-sensitive surface that corresponds to movement through the portion of the symbolic expression, wherein the first flick gesture corresponds to a location-independent navigation input;
• in response to detecting the first flick gesture, moving the focus from the portion of the symbolic expression to a first sub-portion of the portion of the symbolic expression and outputting audible information corresponding to the first sub-portion;
• detecting a second flick gesture outside of the symbolic expression on the touch-sensitive surface that corresponds to movement through the portion of the symbolic expression, wherein second first flick gesture corresponds to a location-independent navigation input;
• and
• in response to detecting the second flick gesture, moving the focus from the first sub-portion of the symbolic expression to a second sub-portion of the portion of the symbolic expression and outputting audible information corresponding to the second sub-portion.

A computing device, comprising:

• a touch-sensitive surface;
• one or more audible output devices;
• one or more processors;
• memory;
• and
• one or more programs stored in the memory and which, when executed by the one or more processors, cause the computing device to determine portions within a symbolic expression, the symbolic expression including at least one portion having a plurality of sub-portions;
• detect a first tap gesture on the touch-sensitive surface directed to the portion of the symbolic expression, wherein the first contact corresponds to a location-dependent navigation input;
• in response to detecting the first tap gesture, place a focus on the portion of the symbolic expression and outputting audible information that corresponds to the portion of the symbolic expression;
• detect a first flick gesture outside of the symbolic expression on the touch-sensitive surface that corresponds to movement through the portion of the symbolic expression, wherein the first flick gesture corresponds to a location-independent navigation input;
• in response to detecting the first flick gesture, move the focus from the portion of the symbolic expression to a first sub-portion of the portion of the symbolic expression and outputting audible information corresponding to the first sub-portion;
• detect a second flick gesture outside of the symbolic expression on the touch-sensitive surface that corresponds to movement through the portion of the symbolic expression, wherein second first flick gesture corresponds to a location-independent navigation input;
• and
• in response to detecting the second flick gesture, move the focus from the first sub-portion of the symbolic expression to a second sub-portion of the portion of the symbolic expression and outputting audible information corresponding to the second sub-portion.