Remember the Reminders
If you aren't using a Reminders or Notes app on your smart phone, you are, well, forgetting some of the phone's most practical features.
Consider that your phone is usually with you. What better place to record the things you think of when you think of them?
Food you need to buy at the supermarket
Tasks you must to do today, this week, or this month
Items you don't want to forget to do or pack for your next trip
Information you agreed to provide for your next meeting
Details you still need to address for your next party
Issues you need to discuss with your doctor, lawyer, veterinarian, accountant, realtor, client, etc
Apple and Android phones both have Reminder and Note apps (the Reminders are part of the Calendar app in Android phones), but there are also other third-party apps available from the app stores.
Find an app that works for you and let your phone do your remembering. Just don't forget to look at your phone!