CuxO-polypyrrole　conductive　aerogel　loaded　on　graphene　oxide　framework　(CuxO-PPy@GO)　with　a　three-dimensional　(3D)　porous　architecture　was　utilized　for　high-efficient　visual　screening　of　H2S　on　a　flexible　paper　substrate.　The　detectable　signal　was　acquired　on　a　portable　smartphone　by　using　a　self-referenced　imaging　platform　equipped　with　the　light　emitting　diode　(LED)　accompanying　an　image　processing.　As　a　proof-of-concept,　CuxO-PPy@GO　aerogel-based　sensing　strategy　was　also　developed　for　Na2S　detection　and　egg　spoilage　monitoring.　Such　a　flexible　paper-supported　sensor　is　expected　for　potential　application　in　portable　and　wearable　food-safety　fields.　©　Copyright　2018　American　Chemical　Society.