31. A non-transitory computer-readable storage medium comprising instructions executable by a processor for: displaying a first portion of digital content on an electronic device; playing a segment of digital content as audio using a text to speech engine while the first portion of digital content is being displayed on the electronic device; and displaying a second portion of digital content if a current bookmark is greater than a last position in the displayed first portion of digital content.
31. A non-transitory computer-readable storage medium comprising instructions executable by a processor for: displaying a first portion of digital content on an electronic device; playing a segment of digital content as audio using a text to speech engine while the first portion of digital content is being displayed on the electronic device; and displaying a second portion of digital content if a current bookmark is greater than a last position in the displayed first portion of digital content. 38. The non-transitory computer-readable medium of claim 31 , further comprising instructions executable to: receive input to change at least one display property of digital content; render one or more new portions of digital content based on the at least one display property that is changed; and display one of the rendered new portions of digital content that corresponds to a text unit that was most recently played or most recently compiled to be played.