Do I need to keep OALD8 on my device once I have upgraded to OALD9?

Existing users of our OALD8 Android apps purchased from Google Play can upgrade to the new OALD9 app for a discount. You will need to have your OALD8 app installed on your device to buy OALD9 at the discounted price. See here for more information: https://oxfordeltdictionaries.zendesk.com/entries/109543846-Can-I-get-a-discount-on-OALD9-if-I-already-own-OALD8-How-

Once you have upgraded to OALD9, there is no need to keep OALD8 on your device and you can remove it if you wish.