Thank you for contacting Ask Extension with your question about spray schedules for apples.
Your first spray depends on what you’re trying to prevent (diseases like apple scab vs. insects like aphids/scale/codling moth). 
In general, The first spray would be during the dormant season / late winter—before buds open—because it targets overwintering insects/eggs and disease spores and beneficial insects are less active then. It's too late for dormant sprays this year.

Here are the main spray times for apples: 
1. Late winter (dormant; before budbreak):
 --Horticultural/dormant oil for scale, aphids, and mite eggs 
-- Wettable sulfur is commonly used for apple scab during dormancy (don’t combine with oil). 
2. Green tip → Pink (just before blossoms open):
-- If you have a history of apple scab, this is when protectant sprays are timed (products vary).
3. Petal fall (after blossoms drop):
This is a key timing window for several pests and is also when codling moth control programs commonly begin.  To protect pollinators/bees, do not spray while the trees are in bloom.
I want to stress that you do not need to spray for all possibilities. Only spray for diseases or insects that have been a problem in the past. I've attached a link to an OSU publication that list the spray times for common diseases and insects. This link will take you to the main document: Click on Apples to get specific information. 
Managing Diseases and Insects in Your Home Garden: https://extension.oregonstate.edu/catalog/ec-631-managing-diseases-insects-home-orchards
(if the link doesn't work, do a google search on OSU EC 631)
You should be able to purchase lures at your local nursery or big box stores.
Happy Gardening!