if(stranded) send(help) end

Just humoring a bit :) Have a nice day!

no one sits on the island and code. The mapping toolbox will direct at least.

A toolbox for modeling physics would be most helpful. Your best chance would be to build a radio capable of sending Morse code SOS into the ether and hope that someone can detect and come save you.

Machine learning toolbox or deep learning toolbox is more better for me. Because it can help 'Wilson's talking.

What first we need: Cooking toolbox!

Me : Give me a MATLAB / ?? : But there's a Satellite Communications Toolb... / Me : M A T L A B

give me a windmill with it

If I am stranded on a deserted island, I don't think there will be electricity and computers, then none of the toolboxes can be used.

What of if you navigate your way to another strange land or probably an unknown destination. Mapping tools might work but what of if you lack the resources needed for the escape or possibly there is a large body of ocean you need to cross to the other side. With the Satellite communication tools, you can always get linked up with any region through space (unhindered) where you could get help from nearby station, probably to be picked up by an aircraft or any other means.

Forget about any other tool boxes. Get a real tool box, repair your damaged boat and escape from the island :D

A aerospace toolbox. Build a plane/heli and fly away ;)

Parallel computing toolbox to run the finite element model of your escape sail boat

A mechanics toolbox.

All of these would only aid in leaving the island if I had time, power, an RF transmitter, a computer running Matlab and more. Why would I want to leave the island then?

Use the Global Optimization toolbox to identify the globe with the optimal position for the current island. Then walk to the mainland via the isthmus.

What do you mean it doesn't work like that?

It's safe to assume we have an energy source, perhaps wired up from a crashed plane or from an underground DHARMA initiative bunker but I'd assume we don't have internet access. Modeling and visualizing satellite orbits won't be useful. Unless we have sensors, signal processing would have limited use, navigation may be important but the current Navigation Toolbox isn't equipped for roadless jungles. The Mapping Toolbox, however, may be helpful to localize your current position which is necessary to plan an escape.

Why, the Wavelet Toolbox naturally :-) (as in deserted island => wavelets)