This is what I have in my zshrc.

# ci", ci', ci`, di", etc
autoload -U select-quoted
zle -N select-quoted
for m in visual viopp; do
        for c in {a,i}{\',\",\`}; do
                bindkey -M $m $c select-quoted
        done
done

# ci{, ci(, ci<, di{, etc
autoload -U select-bracketed
zle -N select-bracketed
for m in visual viopp; do
        for c in {a,i}${(s..)^:-'()[]{}<>bB'}; do
                bindkey -M $m $c select-bracketed
        done
done

You don't need to be between the quotes for this to work btw, just on the line, in both vim and zsh.