As an 'add-on' to Jack's comments, one can replicate the "quote box" often seen in Beesource posts without actually using the "Reply With Quote" button.
What is needed to do that (without the button) is to bracket the text that you wish to see inside the quote box with the BBC "quote" and "/quote" keywords. Note that ALL BBC code needs to be enclosed in square brackets like these: "[ ]".
My example here will substitute the squiggly brackets here as the actual square brackets would get 'executed' and not be visible.
{quote}This is a quoted line.{/quote}
turns into this (when square brackets are used instead of the squiggly ones above):
Note that the quote style above is not "clickable" to link to the source of the quote. If you want to do that, I don't know any way except to use the quote button.
[hr] [/hr]
On my Android phone, there is a 'checkbox' next to the message timestamp (after clicking on a specific message). Once that checkbox is ticked, a sub-menu includes a 'quote' icon (looks like a double quote mark). Clicking on that produces quote code similar to what I show above. At that point, just proceed with preparing your response. Note that non-relevant portions of the quote can be removed by simply deleting the text.
Do Not Delete or Change the BBC Quote code itself.