On April 21st, App Growth Summit held a virtual version for its New York City 2021 annual mobile event. Moshe Vaknin, CEO and Co-Founder of YouAppi, sat down with Louis Tanguay, Founder & Managing Director of AGS, to discuss The Day the IDFA Went Away. Take a look below for our top takeaways from the discussion and feel free to check out the full video here.

Key Takeaway: Although we may see an initially low opt-in rate, once advertisers and publishers adjust, the opt-in rates could increase with time. 

Louis: We’re sitting down with Moshe Vaknin, CEO and Co-Founder of YouAppi. He has been gracious enough to join us and talk about the day the IDFA went away. For this chat, basically, iOS 14.5 is here, ATT is here, IDFA apocalypse is upon us. So Moshe, just jumping in here, what happens now that IDFA has gone away? How does this impact retargeting?

Moshe: First of all, it really depends on how advertisers and publishers will react on the first day. Some are prepared and have created messaging according to the protocol that Apple instructed, and some are still waiting. According to some statistics, the opt-in levels could go up to 40%, but that may take some time. So, the immediate reaction we may see is a decline on iOS capabilities for retargeting. But after a while, I truly think advertisers and publishers will adjust and begin to improve the opt-in levels. 

Louis: Great, so going off of that and getting a little bit more in the weeds. How do you think retargeting is actually going to work without IDFA?

Moshe: I think obviously the objective of IDFA according to Apple is to try and get consent from the user so they agree to be tracked. But I think the objective of what Apple is trying to do is good. But still there is a need for information, such as Device ID, so we can drive appropriate targeted content and ads, and for retargeting to help advertisers reach their audiences in a better way. The question is, how far Apple will go and allow flexibility with the message, that publishers and advertisers can share with the users. If they are flexible, I think the opt-in level will go up. Contextual targeting alone will not drive the results and accuracy that we are looking for. Retargeting helps advertisers see accuracy. So these strategies in combination with opt-in may help advertisers see what they’re looking for. There are currently some restrictions from Apple, such as that the advertiser can only show their messaging once, so there is some uncertainty. Yet, I’m optimistic that we’ll find a formula.

Louis: You bring a good perspective that even if the opt-in rates are low at first, they could still improve. Also another good point is that if Apple only triggers this once, and you only get one shot at this, and the opt-in rate is low, then do we think Apple may give the advertiser another chance such as with the next update?

Moshe: Sometimes a user doesn’t understand the impact at first, so it makes sense and is realistic that Apple may give the user a few chances. 


Key Takeaway: Implementing a combination of User Acquisition and Retargeting remains an important strategy in an IDFA-less world. 

Louis: Yeah, I think if Apple is truly on the publishers’ side and they realize that there is low adoption rates (if that’s the case), then they may be motivated to allow a re-push for ATT approval with an app update. Implications of an IDFA-less world, how do you think performance marketing may be affected given we wouldn’t be able to target users based on interest as reliably as before? Do you see us shifting more toward brand messaging, especially for retargeting as well? Or do you think there’s enough there that we could work with? 

Moshe: I believe we would need to implement a combination of User Acquisition and Retargeting, which is currently what YouAppi is doing. It’s not necessarily brand messaging, it still falls in the arena of performance marketing. That really is the new model, so the publishers would need to adopt to this, and advertisers would need to agree to, and the tracking process would need to be adopted to this model. So companies who can do both UA and Retargeting on the same impression could benefit from that. 


Key Takeaway: Utilizing specific messaging and creative optimization could help you reach the remaining users who may not have opted-in. 

Louis: So we mentioned earlier that the projected opt-in rate could be anywhere from 20-45% by a recent MMP research report, I actually think there’s good evidence it might be lower, so how do you think we would reach the 55% that do not allow ATT approval?

Moshe: It could cost advertisers more money to target specific users. With contextual targeting for example, if 80% of your users are coming from sports channels or music categories, then you would target this specific group of users. So there is a good chance you could reach 50-60% of these users if you are focusing on the right category, and utilizing specific messaging and creative optimization to push this number higher. 


Key Takeaway: Focus on framing the language and messaging of your pre-ATT prompts in a way that is educational to the user. 

Louis:  So we’ve seen a various amount of advertisers and publishers attempt to get IDFA approval from their users. The most effective that I’ve seen is from Facebook where they put up an interstitial that said that your iOS is about to change the way you are served ads, and we want to serve you more personalized ads. So they ask you for permission, and the user has to say “okay, serve me more personalized advertising,” and they put it in the same language as the apple prompt. The information here is contextual and helpful, and it puts you at ease. But, I’m concerned that some publishers won’t be as thoughtful as Facebook was to educate users to the point of acceptance. If they say “no” at the interstitial, then they don’t have to force the prompt. But if they say “yes” and are led to that prompt, then putting that button in the same language as Apple’s prompt will be very helpful. 

Moshe: What you just described is exactly the point. Although we don’t know yet how flexible Apple will be, we can assume that if Apple’s objective is to get consent from the user then this may be allowed and some flexibility for messaging is needed. Some publishers will interact with their users in different ways, they have different content and different objectives. And they need to have freedom to tell the users that I need consent so I can simply make more money from the data that will be targeted to you, while protecting your data. There must be communication and understanding between the users and the publishers, as well as trust.

Louis: If there are one or two things you could tell publishers to take into action right now, or even just some reassuring thoughts, the floor is yours.

Moshe: They should be active, some are waiting and seeing. But if you wait and see, nothing will happen. You have to be active, be involved in the creative process and the messaging, work with your partners. If you take an active stance, there’s a good chance you will have a high opt-in rate. 


  • Even if the opt-in rate is initially low, it can increase as publishers and advertisers adapt to the new changes and implement growth strategies.
  • A key model to follow is a combination of User Acquisition and Retargeting for achieving growth.
  • To reach users who have not opted-in, focus on improving your messaging and creative optimization. 
  • Frame the language and messaging of your pre-ATT prompts in a way that educates the user on why they should opt-in and what opting-in means for the quality and personalization of their advertisements.  

Stay tuned for the next App Growth Summit event in your region!