[#TWITTER](/relevant/new/TWITTER) Some iOS Twitter users will see up and down votes on comments as parts of research "to understand the types of replies you find relevant", the social network says. [#RELEVANT](/relevant/new/RELEVANT) ???
[#TWITTER](/relevant/new/TWITTER) Some iOS Twitter users will see up and down votes on comments as parts of research "to understand the types of replies you find relevant", the social network says. [#RELEVANT](/relevant/new/RELEVANT) ???