Best practice for switching viewgroups in fragments

Hi i've created an app that i'm rather proud of yet one big part of my app i have had to labouriously create piece by piece and id like some advice on how to approach it better.

What i want to achieve is 2 containers, one at the bottom 'bottom container' with images 'to be selected' and one at the top 'top container' with images that 'have been selected'.

The 'to be selected', 'bottom container' would change depending on user input (selecting an image) and the 'have been selected', 'top container' would be empty to begin, but would save and display that user input (selected images),

I want these images to have strings attached to them, selecting an image from the bottom container puts it in the top container, and saves the string in a new string (string X) the bottom container then displays a new set of images.

These new images in the bottom container have new strings attached, and pressing one of these images would put the image in the top container next to the last selected image and saves the new string with the old string into string X.
String X is always passed to the android TTS engine and should play when the speech bubble button on the right is pressed (see screenshots)

So this would be the first shown activity

If the first button was pressed the screen would look like this:

If the second button was pressed it would look like this

Im really not sure the best way is to implement this,

Right now every time an image is pressed it opens up a new activity and every time the speech button is pressed it plays a soundpool that i have created, so i have roughly 90 different soundpools from 2 to 5 seconds which is loaded into memory each time which is a heavy resource on the system and leaves it very inflexible!

I dont have any real experience in java or android other than what ive learnt myself so any opinions would be appreciated i just have all these ideas of how to get it done and they keep ending in dead ends after hours of development.... But i guess im learning more for it. Any and all suggestions welcome. Many thanks,