10 Reasons a Tactile Home Button is a Must

upside down phone - how can you tell? what if your life depended on it?

1. Can wake the phone with one hand and one finger - even wearing gloves!
2. Tap the screen to wake? Then: phone keeps waking up in your pocket!
3. Ability to answer the incoming call even if your screen is cracked
4. Phone is still useful if you are blind or disabled
5. So you don't have to keep flipping the phone around
   1. when you pull out of your pocket upside down
6. So you don't accidentally press it twice
   1. Sometimes your finger taps but misses a touch button, and it requires a second tap attempt. This ambiguity is not possible with hardware, and in software even the slightest delay could potentially perceived as a missed tap, causing the speedy user to tap again.
   2. Within about 40ms is the maximum delay before the brain registers (about 2 clicks during alpha brain state). Probably these decisions are made based on the old industry standard 700ms for a "frozen app" perception upon a virtual button click, but that is an old standard, and this is a high performance mission critical button.
7. Ability to rapidly switch out of phone app to perform another task during phone-call or full-screen
   1. How do you get to home when in fullscreen mode?
8. Reduced accidental taps when typing quickly
   1. It is so distracting when typing extremely fast to suddenly be shown the home screen!
9. Some Android versions you can get a task manager by holding the home button down.
10. Phantom touch screen blindness. I've missed calls due to this on slow phones.
11. Easy to tell  visually if the phone is the right way up when screen is off.
    1. Look at this image, is the phone the right way up? You sure about that?
    2. What if your life depending on it? What if you needed to make an urgent call in a stressful environment? Or if you hand had been chopped off? I can answer my phone with my teeth if I wish.
12. Snooze / Wake / Dismiss alarm with home
13. Screen must be active to work. Capacitive touch requires charge. They must use more power!
14. A place to rest your finger that won't immediate do something unwanted!

That's all for now. Here is a video of  a Nexus 4 sliding off a completely flat surface!

Downsides

Ask yourself - are any of these downsides user centric? Or Is this list more of interest to manufacturers:

• Mechanical breakages and reliability
• Screen real estate
• Motherboard space
• Waterproofing
• Requires more force to activate (this can be a benefit!)

Most people would like a reliable phone, but even for those who shop purely based on ruggedness and reliability, information on the subject is sparse, with no standards to measure reliability of buttons. A standard does exist for waterproofing.

Further Reading

https://medium.com/design-idea/software-hardware-and-capacitive-buttons-6bff3e8f9765

https://www.zdnet.com/article/thank-you-apple-and-samsung-the-physical-home-button-is-essential-for-efficiency-and-security/