Flexible　and　lightweight　supercapacitors　with　superior　mechanical　flexibility　and　outstanding　capacity　are　regarded　as　an　ideal　power　source　for　wearable　electronic　devices.　Meanwhile,　incorporating　additional　novel　characters　such　as　transparency　and　electrochromism　can　further　benefit　the　development　of　smart　supercapacitors.　Nevertheless,　the　application　of　the　commonly　used　planar-structural　current　collectors　is　seriously　restricted　by　their　intrinsic　properties　such　as　poor　rigidity,　large　thickness,　and　limited　loading　surface　area.　Flexible　and　ultralight　current　collectors　with　3D　architecture,　high　conductivity,　and　easy　integration　are　believed　to　be　the　most　appropriate　alternatives　to　build　high-performance　supercapacitors.　In　this　study,　a　novel　and　scalable　manufacturing　technique　is　developed　to　produce　a　flexible　and　ultralight　3D　Ni　micromesh　(3D　NM)　current　collector　for　supercapacitor.　Flexible　smart　supercapacitor　integrated　by　3D　NM　and　high　active　Ni-Co　bimetallic　hydroxide　(3D　NM@NiCo　BH)　delivers　a　considerable　rate　performance　(60.6%　capacity　retention　from　1　to　50　mA　cm(-2)).　Furthermore,　the　fabricated　hybrid　supercapacitor　device　integrated　with　electrochromic　functionality　can　visually　indicate　the　energy　level　by　a　color　display.　This　flexible　electrochromic　supercapacitor　based　on　ultralight　3D　Ni　micromesh　provides　a　novel　insight　into　multifunctional　energy　storage　systems　for　smart　wearable　electronic　devices.