Low memory

Hi all,
I have a small size of RAM in an embedded system ans using BusyBox. I need to run multiple applications but those all don't fit on the device. When all began running I get a low memory condition. Some of these applications needn't to be up for all the time. They'll be used once in a month for a few minutes.
What can you advice me to do?

thanks in advance

Are these applications code in your control? so you could modify them for a smaller foot print.
Can you use a swap partition? With a manager for managing your processes.

Write a manager for your processes to check what is running and certain parameters to shutdown and then re-start while other processes are having to be run.

What do you think?