Solutions (though not the reason behind) are explained e.g. on Appslova.com. Taking a look at them, those are more or less the "Generic Google Play Solutions":
- Go to Settings→Apps, Select “All” tab
- Find Google Play Store, open its entry, Clear Data and Cache
- Find Google Service Framework, do the same
- Now restart Google Play Store and try to download/update the app or games
- Open Google Play Store
- Go to Settings→Accounts, Choose Account or add new account
- Now try to download or install the app or game
- Go to Settings→Accounts→Google, remove your Gmail account
- From Settings→Apps→All: Force stop, Clear data and cache for Google Play Store, Google Service Framework and Download Manager (like in method 1)
- Again, go to Settings→Accounts→Google, Add your Gmail account
- Restart your android and then accept all the Google terms and setup Google settings
- Run Google Play Store and update or install your app.
Some more hints are to be found in Google's product "forum". Reasons here were e.g. storage full: Clean up, delete stuff, try again, worked.
Find a bunch more hints, all on the first result page to a Google search on "google-play error 498" :)