I wish PRS-T4 has following features (in addition to features in T3)
Software
1. Tap to turn page. I found tap is easier than swipe.
2. Vocabulary builder as in new kindle.
Hardware
1. ~150 g or less weight.
2. Front light.
If not, T1/T2-like light case with adjustable light intensity.
Old light case is easier to adjust LED position
and to separate ereader from the case than the current one.
I pop out my T1 from the case in lighted environment
because the naked T1 is feather-like, thus easier to hold.
Software
1. Tap to turn page. I found tap is easier than swipe.
2. Vocabulary builder as in new kindle.
Hardware
1. ~150 g or less weight.
2. Front light.
If not, T1/T2-like light case with adjustable light intensity.
Old light case is easier to adjust LED position
and to separate ereader from the case than the current one.
I pop out my T1 from the case in lighted environment
because the naked T1 is feather-like, thus easier to hold.