The first Nokia devices, Nokia 3, Nokia 5 and Nokia 6 are now receiving quarterly security updates from Google, and the support will end with the year 2020. But, the first Nokia smartphones launched by Nokia Mobile are now in the fourth year of security updates which is something not many manufacturers will be offering for its products. Nokia 3 just started receiving September security patch which should be available globally. It came to our Nokia 3 and it is 83.71 MB large. But, some owners of Nokia 3 reported receiving the same update but with software package being over a GB large. Anyway, the size of the update depends on the model number and market where the device is used, so probably there is a lot more security issues for specific markets that need to be patched and that shapes the size of the update.
In the mean time, I checked Nokia 5 and Nokia 6, and the update is still not available for those legendary Nokia smartphones. Anyway, If you are still hanging on to your Nokia 3, do check if the update is available and make it safe once more.