Credit unions are pouring money and resources into mobile these days, but budget pressures, constantly changing technology and big learning curves sometimes mean their platforms end up doing more harm than good.

It's no surprise, however, that many credit unions have scrambled to "just get something out there." In 2011, four out of five people didn't use mobile banking; now 35% do, according to a Federal Reserve study. People are also using mobile banking more often – 45% said they use it at least once a week, an increase of 37% since 2013, according to RateWatch. So not only is the mobile market getting bigger, it's getting more ingrained in members' day-to-day lives, and in turn, it's becoming the technology that could determine whether a credit union lives or dies.

But talk to some of the firms credit unions turn to for help fixing their existing mobile technology, and you'll hear stories of clunky design, botched attempts to build apps in-house and backfired efforts to pinch pennies. These gaffes can have big consequences, but they also point to seven dos and don'ts that experts say credit unions should consider carefully to make sure their mobile technology actually adds value.