

Ads can also be voluntarily viewed to finish charging a hammer power-up or to earn gold. Every four or five levels, players have to look at another in-game ad. The only distracting element of Angry Birds Stella is the prevalence of ads. The use of gold isn't overwhelming, and I earned more gold than I needed just by playing the game. Gold can be used to buy additional birds, buy powerups or skip level barriers. In certain levels, gold helped me save birds and focus on practice. Gold is earned by gaining stars and beating level sections, and can also be purchased in-app. That's where gold, the in-game currency, comes in.

It's likely that the two will cross at some point and that I will eventually have to pay for birds. This limit didn't affect my enjoyment early on, but as I got further into Angry Birds Stella, I noticed that the difference between the number of stars needed and the number of stars earned had narrowed. Otherwise, they can buy additional birds with in-game gold or with Telepods, the interactive-toy versions of Angry Birds characters. On level 12, players need to have 18 stars to get the first extra bird, and 12 to get the second. Instead, players start with only one or two birds per level and need stars to get additional birds. However, Stella doesn't use stars to limit the number of levels. Stella uses the same 3-star rating system as past Angry Birds games, and players are encouraged to get 3 stars before progressing further. The ability to think through gameplay really improved the experience for me as a whole. Angry Birds Stella gives you a few extra seconds to aim a bird for a perfect shot. In earlier versions of Angry Birds, players relied on a randomized mechanic in which a split-second tap was the only control to determine where a bird went. For example, Stella's special power is the ability to bounce from structure to structure. All of the birds' powers use a new aiming mechanism to add a strategic element to gameplay.

Surprisingly, Stella breathes some fresh air into the mechanics. After seven-plus renditions of Angry Birds, you'd think Rovio would have run out of ways to change it up. Angry Birds Stella uses the same mechanics as most Angry Birds games you load a bird into a slingshot and fling it into a structure full of pigs.
