Pixeljima Dev-Blog: Lessons from user experience testing

During the development of Pixeljima, we had a small number of volunteer, part-time testers.  Apart from direct feedback from these players, watching these players play was quite valuable.


In the game we have a screen where there is a picture of a hangar with a tempting question mark in the middle.  At the bottom of the screen is a button to spend 100 stars (in-game currency) to buy a random prize.  We observed players touching the question mark to activate the purchase, so simply added that as a hot-spot that did the same thing as pressing the button.

Other screens had timers which would move on to another screen after some animation.  When the timer was too long, the player would touch the screen or press the back button to try and move the action along.  The threshold for this "what's next" response is sensitive to within a second.  e.g. shortening the delay of moving on to the next screen by a second, removed the "whats next" response.

The game was designed to be hard.  In game design terms this is the concept of Fiero, hard fun.  There are only six levels, and there is a progression system in the game where you get better planes, better armour, better firepower, etc.  Also, they player's skill gets better as they learn the levels and the hazards to avoid.  One direct tester feedback we has was to make the start of the game easier.  Another direct feedback was to make the start of the game harder!

We found it depends on the player skill level.  A skilled player can take a non-upgraded plane through to level 4.  This kind of player wanted more challenge up front.  Lower skilled players were getting destroyed in a few seconds, and getting frustrated.

We solved this in two ways:  First we made the first half of the first level much easier.  It ramps-up in difficulty.  e.g. the first wave of planes don't shoot at you, the next wave only shoots after 12 seconds, the next wave after 9 seconds, etc.  The first waves that shoot fire half-speed bullets.  Then three-quarter speed, etc.  It's not until half-way through level one that you encounter "normal" strength enemies.  This gives new players more hope, it gives them longer to practice basic skills, and importantly - gives them access to the first mini-boss, and first POW pickup.

The second way was built into the game design, as players unlock new planes - they will encounter planes that are weaker at the start - which are much harder to get through the levels - which provides a greater challenge to experienced players.  So, the player that could breeze through to level 4 with an un-upgraded Lockheed P-38 Lightning, would be happy to reach the first POW pickup with a Brewster F2A Buffalo.

A friend of mine pounded the desk with his first and exclaimed, "I hate you!", because they couldn't get passed the first level.  I said if you hate me because the game is hard, I'm ok with that, but if its because of bugs then that's not ok.  His main complaint was that he couldn't see his plane under his finger, and additionally couldn't see enemy aircraft coming up from behind.  I inquired if he had discovered the control scheme setting in the pause menu.  He hadn't.  He changed control to "relative", then he could fly with his finger beside or under the plane.  He found that so much better.  The lesson here was to change the default control scheme to relative.

Another tester spent the first few games avoiding stars, which are dropped in-game and meant to be collected.  These provide currency to buy upgrades and new planes, and rank up the player.  To help with this we put a spin and sparkle animation on the stars, and we added a "tutorial message" system for new players - which offers advice like "collect stars", "avoid bullets", "POW's increase firepower", etc. at the start of each new game. 

One of my friends, after the game was in soft-launch, said, "I'm not buying your upgrades!".  I told him he didn't need to because he can get them for free.  "What?".  Yes, if you collect 100 stars, you can unlock a random plane or upgrade for free.  He hadn't noticed that option.  The banners at the end of game are random, and so you aren't always offered the option to spend your stars on a prize.  So I decided to make the banner always appear the first time you have 100 stars or more, and to grey out the rest of the game and make the player purchase a prize - in that way showing them an important game mechanic - and one of the key reasons to collect more stars.  Given that he is already frustrated by level one, and now knows he can get upgrades, I'm sure in time he will actually purchase something after perhaps another 40 games.

Finally, younger players can provide good unfiltered feedback on your games.  I've had a nine-year-old player play for 50-minutes in one session, and note that they were "determined!" to reach level 2 (this was before the difficulty level of level one was reduced).  Also, 50-minutes is pretty near the maximum attention span for a child of that age, so a good indication the game was engaging enough to keep trying.

Some feedback we haven't been able to address (yet).  For example, we haven't been pedantic in the resolution or colour palette - and have identified a few UI elements that we want to improve.  One screen has an annoying response delay which requires code to fix.  So things get prioritised, and worked on as we are able - but we felt it was better to get the game out and continue to iterate, rather than keep it under wraps and get buried under the always growing list of enhancements that could be made.

One thing is for certain though - user feedback, and observation of user interaction with your game, is a fantastic source of information to make your game better.

By Stephen McIntyre


Pixeljima on App Store

Pixeljima on Google Play Store