There's been a steady shift away from blind sources towards trusted sources. However, whether this is a universally effective approach is uncertain. Because directing marketing budgets exclusively to trusted sources is not always economically feasible, these type of ad campaigns tends to be quite a bit more costly. It’s also important to consider their effectiveness, taking into account such KPIs as CPI (Cost Per Install), LTV (Lifetime Value), fraud rate, ROI (Return on Investment), and their interrelation.
Marketing via trusted sources has some clear advantages. They allow conducting highly targeted custom-tailored ad campaigns via a wide range of ad tools (banners, video, playable ads, etc.), generally engaging a much more relevant audience. And, at least for now, they are less affected by fraud.
But there are also disadvantages, namely, higher CPI (Cost Per Install)/CPA (Cost Per Action) rate and higher entry thresholds (for example, video ad networks have a minimum budget requirement to run an ad campaign). And where there are increased budgets we can expect a higher incidence of fraud.
It is reasonable to say that in certain categories of applications purchasing traffic from blind sources may be more cost-effective and impactful than purchasing it from trusted sources. This is particularly applicable to mobile games and e-commerce industries, where social and video ad networks appear to pack the most punch.
Consider this: when buying the same number of installs for a mobile game from trusted sources (CPI=$3.5) vs. blind sources (CPI=$1.2), the total revenue from users acquired from trusted sources appears to be higher. However, when we take into account the customer acquisition cost (CAC) and calculate the average revenue per user (ARPU), then the total revenue can be up to 20% higher for users acquired from blind sources than from trusted sources.