oh my, do you *really* want to ask me that ??? i won't tell you which are *popular* necessarily (i don't really follow the trends much) but i could give you a list longer than your arm of writers i love. i don't know if they are all translated though. here are a few of my favourites if you want to scout around :
Raymond Queneau (a veritable silversmith of words, hats off to his translator if there is one for the challenge alone) for a short one you could try "exercises de style" or "zazie dans le métro" which i recently re-read, my god, the man was brilliant, and it's great to re-read it because now that i'm older (and more worldly

) i noticed dozens of jokes and allusions that somehow when right over my head when i first read it. zazie was also made into a film.
Léo Malet : wrote the Nestor Burma detective series "Nouveaux Mystères de Paris", one of my all-time favourite detective writers, sadly, not yet available in ebooks. another genius of language and little jokes (many of which i noticed / understood only after several readings).
Boris Vian : a true genius, writer, poet, musician, jazz chronicler, translator of Raymond Chandler into french... try "l'écume des jours" which is probably his most famous book but he also wrote a metric tonne of short stories.
Fred Vargas : definitely translated, not sure if she's available digitally. she writes mysteries as well, i LOVE her work, another excellent wordsmith and very philosophical, her mysteries are gripping and intelligent with lots of strange digressions into random (or not-so-random) musings. thinking about it, i suspect you would really like her work, definitely take a look.
on feedbooks, i doubt that most of the contemporary writers have been translated (there are quite a few of them and many of them are members here too, like Irène Delse), but some of the classics are, like émile gaboriau (father of the detective genre ! yep, before conan doyle...), i discovered him there and he's quite good. watch out for "Monsieur Lecoq", it's over 700 pages long, starts out a mystery, then goes into historical melo-drama for 2/3rds of the book and the mystery is resolved in the last 2 pages.
