The needs defined the basic foundations of the project, the functions defined the project requirements and the functional specifications quantified the functions. Now is the time to come up with solutions by way of brainstorming, far fetched ideas can often trigger more realistic potential solutions, so anything goes:

• Laptop
• Standard tower desktop
• Raspberry Pi
• BeagleBone
• NUC
• iMac
• Mac mini
• Tablet
• iPad
• ...

In this non-exhaustive list of solutions there are obvious bad ones which are immediately filtered for good reasons:

• Standard tower desktop: too cumbersome to transport
• BeagleBone, NUC, iMac, Mac mini, iPad: too expensive

This leaves the Raspberry Pi, laptop and tablet as realistic solutions. They all have advantages and disadvantages:

Raspberry Pi

• Advantages
  • Cheap
  • Lightweight, but needs peripherals
  • Maintainable
  • Has Wi-Fi
• Disadvantages
  • Requires a screen with HDMI or DVI input
  • Needs a HDMI-HDMI or HDMI-DVI cable
  • Needs mouse and keyboard peripherals
  • Needs a 5V power supply
  • Needs an SD card of at least 8GB
  • No backup system
  • Needs preparation

Laptop

• Advantages
  • Lightweight
  • All peripherals are included (screen, mouse and keyboard)
  • Battery provides power backup
  • Robust
  • Has Wi-Fi
• Disadvantages
  • Expensive
  • Not maintainable

Tablet

• Advantages
  • Lightweight
  • All peripherals are included (screen, mouse and keyboard)
  • Touchscreen
  • Battery provides power backup
  • Robust
  • Has Wi-Fi
• Disadvantages
  • Expensive
  • No physical peripherals (keyboard and mouse)
  • Not maintainable

We now have a choice between three somewhat objective solutions, however to select one of them we need to look at the total cost of what it takes to buy and transport them to Malawi...