You could use ACF’s built-in form functionality (see: http://www.advancedcustomfields.com/resources/tutorials/creating-a-front-end-form/). If you want more fine-grained control, I know others have used ACF with Front End Edit (https://github.com/scribu/wp-front-end-editor), which is probably the most popular and stable plug-in for inline editing.
You could also try a plug-in I’ve been developing, X-Editable-ACF (https://github.com/wells5609/X-Editable-ACF). I can almost guarantee you’ll run into bugs or something that doesn’t work, but its worth a look if you’re comfortable with PHP.
