Test result: Success. The character lower limit for both title and content is 1.
Details:
If both the title and content have no character, the 'Next' button is greyed out and the 'Left Arrow' button sends you back to the list of chapters, without saving anything.
If the title is less than 1 character long and it has never been saved before , the 'Next' button is greyed out and the 'Left Arrow' button saves the chapter in the 'Drafts' section. The title is automatically replaced by 'Unnamed', and if tried a second time, the chapter will be published with this title.
If the title is less than 1 character long and this chapter has already been saved before (the title has been erased), the 'Next' button is greyed out and the 'Left Arrow' makes the mention 'Please input title' appear at the bottom of the screen. It is then impossible to save the chapter again without complying.
If the content is less than 1 character long, the 'Next' button is greyed out and the 'Left Arrow' button makes the mention 'Please input content' appear at the bottom of the screen. It is possible to overwrite this condition by pressing the 'Return' button of the smartphone, however some problems will occur : 1) The chapter will be saved locally, but not on the Webnovel server, as explicited by the 'NOT UPLOADED' red mention next to the chapter title. 2) The word count will be displayed as 'null' if the chapter has never been saved before, and '0' if it has been saved before and modified. 3) Every time a chapter is being saved as a 'Draft', the prompt 'need content' will appear at the bottom of the screen. The prompt will appear once per chapter without content, and every new prompt deletes the precedent.