"Whoever stops becoming better has stopped being good" - this quote, originally from Philip Rosenthal is what a good product development describes. Only a product which gets improved permanently will be successfully in a longer term.
To record your ideas and problems, create a new pinnery board with the columns Ideas and Problems. So the product developers know, what to do. As soon as someone begins working on a task, he drags the card to the In Progress column.
If the work is finished you can drop the card to the Test board. Your product testers know then, which features they should test. After finishing the test the card gets dropped to Done or Problems again.