If your app is laggy on an android emulator, does that mean it will be laggy on a real device? -

i new making android apps , i'm making app , testing on whole bunch of emulators. emulators run smoothly , app lag free when try make own emulators (i search specs device online) app becomes laggy. emulators android studio came work fine app though. if app laggy on these emulators i'm making specs online, mean app laggy on real device of kind?

example:

i made emulator samsung galaxy grand prime with:

• 5.0" diagonal screen length
• 540x960 resolution (auto filled large, long, , hdpi)
• 1.5 gb of ram
• 64 mb of vm heap
• 800 mb of internal storage
• sd card studio managed 100 mb

my app runs fine on nexus emulators android studio provided samsung galaxy grand prime emulator, app laggy.