Hi guys,
I've checked out the beta on testflight for this function on my iPhone 6S. I think you've done a great job on it: in the beta it's already much better. You can now slide without your thumb obstructing the characters, and the larger font is easier to read than before.

I would suggest:

(1.) De-selection: Sliding down/up more than a certain amount (e.g. to the middle part of the keys in the row below) ought to turn off the selection highlighting.

(2.) Normal/unaccented character already selected (in case of accidental activation):
Some users may linger on the key a bit longer than most users, even when they want the normal unaccented letter (e.g. when swiping, or older people/children). Currently Padkeys types nothing, whereas the Apple keyboard types the normal letter. Thus I recommend having the unaccented character in the popup menu too, already selected, as per the Apple keyboard. Slide off to de-select.

(3.) Move the key popup menus for u, i, o, k, l, comma, period [English layout] to the left of the letter key. Particularly in regard to point #2: it would look silly to have the unaccented letter in the middle of the accented letters.

(4.) Activation Delay: I suggest slightly increasing the delay before the accent menu activates, [especially if you really don't want to do (2.)], so that it doesn't activate when the user wants the unaccented letter. I think on Padkeys it currently activates a bit faster than on the Apple keyboard.

(5.) Font Size: [iPhone version] If there is room to make the font one or two points bigger still, it would help with readability of accents. If the font were to remain the same size as the large initial letter popup (if there is enough physical space), many users would be grateful.

(6.) Contrast: When the colour theme has black text on the keys, use a lighter highlighting colour for more contrast. With white text, the contrast is fine, but a bit more contrast won't do any harm. Alternatively, the highlighted letter could change to white text, like the standard Apple keyboard does currently.

(7.) Number keys: The popups for the number keys ought to be moved as far upwards as possible, to prevent obstruction from your thumb. I think there is still 1mm of spare space! :)

(8.) Degree Symbol: [low priority] I would add the degree symbol to the zero key's popup menu. Possibly also to the letter "o".

(9.) The superscript and subscript numbers are a welcome addition. Now we can type H2O, CO2 etc., with a subscript 2! It would be a good feature to advertise, I think many people would buy Padkeys if they knew about it!

(10.) [Low priority] If you really want to appeal to the geeks, add subscript letters, (physical space permitting. I think for the iPhone version this might only be in landscape mode.) :)

(11.) If after all this, there is not enough physical space for the popup menus (particularly on the letter "o"), you could consider putting the hyphen, underscore and en-dash on a second, higher line. Sliding upwards would select them, (even if one's thumb is actually on ó or ö: the whole point of this thread is that the highlighted area ought to be higher than one's thumbnail, not obscured by one's thumb). (I think most people type the hyphen and underscore using the Option key anyway.)

Well done guys! (Am I imagining it, or has the Apple keyboard changed behaviour slightly? Maybe they read this forum? :) )

On the top row, it's less important to raise the height of the popup menu, as to lower the bottom of the popup menu, so that you can slide your thumb sideways and see the character without your thumb blocking it.

I agree, if you decide you don't want to type the character, you should just be able to release it. On the Apple keyboard, if you decide you don't want to type the character, you slide downwards off the menu. On Padkeys, might have it that returning to the site of the home letter then releasing will cancel the operation. This would still work with a slider control. e.g. if you hold the letter "i", a slider control appears with the knob at the far right setting, the accented forms are located where the digit keys for 3-8 are. Releasing without sliding will cancel, and sliding the control or sliding to the character will select it.

Something similar to the Apple popup would be great: perhaps you could replace the Apple keyboard's unaccented character with one of the following:
– a blank space (meaning "type no character")
– nothing: this location is outside the menu
– an X in a solid (red or white) circle

It would be good if the sensitive area on the "hold-and-slide" pop-up menus were as big, with as much space (especially below the character) as they are in the standard Apple keyboard, and they replicated its behaviour.

1. Our thumbs obstruct visibility of the "hold-and-slide" symbols with the Padkeys keyboard (at least, it does on an iPhone 6). Try typing é or è. It's difficult to see, as your thumb is in the way. Now try it with the Apple iOS keyboard: it currently has superior behaviour. It has a wider blank area below the characters è é ê ë where you can slide your thumb. It even allows you to slide your thumb downwards off the menu to see the whole character! It allows you to simply slide sideways to select the character, instead of having to slide up first. It would be great if you could replicate these little points. In fact, you might even like to put a slider control below the characters to make it obvious that one can slide left/right without having to slide upwards! (This might require adding the unaccented character, in case you decide you want no accent after pressing it)

2. Secondly, accents, being smaller, tend to be hard to read for users with poorer eyesight (especially on an iPhone). Making the characters on the pop-up menu keys larger would help (at least on the iPhone version). They can be larger than the normal keys, as space is not much of an issue when selecting accents!