Old discussion but still relevant... Glad I believe in the resurrection
As a regular plain old member, I really never used the LDS tools app. The need to look up other members of the ward just doesn't come up very often when you don't have a leadership or missionary calling.
Well, I just got a leadership calling and you can imagine my disappointment when I discovered the LDS Tools app no longer worked on my SP4.
One of the previous comments suggested it was not trivial to secure private membership data that is downloaded to the device. I disagree. Encrypting the data can be as simple as compressing it in a password protected .rar format until the app is opened (just a little more CPU/RAM overhead to decrypt it). And mobile devices already encrypt their local storage. What is not trivial is passing privacy regulations. That requires more than just securing the data, it requires rigorous testing and validation by licensed security auditors, and those people need to be paid. And usually these audits have to be performed annually. And the paperwork involved..... Based on other previous comments, it's entirely a matter of the church leadership not being willing to pay the auditors. (I work in IT, and some of my customers have to maintain HIPAA compliance and OH MY GOODNESS!)
It's simpler with iOS and Android (and even Windows Phone) because the local storage is already encrypted, and that's enough to satisfy most privacy requirements. For PCs and Windows tablets, however, the local storage is not encrypted by default, so the only protections offered by the platform are NTFS permissions, which are so easily circumvented.... let's just not go there. (Nerds might be interested to know that the current edition of LDS Tools data is encrypted by the Legion of the Bouncy Castle.)
But given the evolution of MLS, I suspect that the church is moving towards a web-based platform for PCs. While Microsoft is pushing (and intends to move entirely to) the new app Store platform, the church hasn't embraced that move. Most of the church's clerical computers are still running XP.
The link from within Gospel Library does still work, so I'm grateful to still have the app available to use. As long as the data source retains the same URL and format, the app should continue to work fine. Just don't talk about it too loudly, or someone might remove the link in a Gospel Library update....