What device are you testing on? Define what is laggy? What are your building with? Frameworks, versions, etc.
Desktops are still more powerful than mobile, so this is not unexpected. There could be lots of reasons for poor performance. heavy DOM, poor code design, bad framework choices, etc. It could be the webview is old and poor as well, and you might need to look at Crosswalk or WkWEbview as solutions.
Currently, I'm using no libraries, anything like that, I'm testing on a Samsung Galaxy S5 (Android 4.4.2), it works fine even on the mobile browser, if you'd like to see the code, I can post it here, or provide a link. The kind of lag I'm talking about is general slowness, it's just running slow, and sometimes, even slows down more for a few seconds, some things do appear to be running at normal speed (i.e. spikes spawning at the correct times) I can tell because they spawn closer together than normal, if you need more information, just ask.