I downloaded the ACSM ebook file on Adobe Digital Editions. What's frustrating is that you cannot use keyboard spacebar key, left or right arrow keys to page up or down properly. The keys work, but each time you pressed any of the keys, you have to move your eyeballs to find the correct location on where you last read because the keys doesn't jump from screen to screen (like in web browser) in zoomed x2 view (default page view text font size is too tiny to be read by myself and most people, especially students and staff who have poorer vision or disabled). Scrolling on the trackpad is inefficient and frustrating. This wastes students' time and hinders their learning progress (some do not know or think of going back to use spacebar and SHIFT + spacebar key in web browser). Separately, the issue with web browser is that you have to keep signing in again and again and thus lose your last read placement as it doesn't have the advantages of the offline Adobe Digital Editions app. Naturally, one can search the browser's webpage for the ebook page no. or scroll to last read page number, but some students doesn't know how to do that thus demotivating them.
This may seem like a minute issue, but given the amount of ebooks a human will read from his, her or gender X's toddler years to bachelor's degree beyond into PhD and lifelong learning, the tiny inefficiencies amount into an exponential amount of wasted time and productivity that otherwise can be redirected into profitable ventures that benefits the self and the nation.
Time is money. Well read students can learn more effectively in half the time when the forementioned issues are surmounted.
Please kindly feedback to Adobe management team regarding their app issue which decreases their profitability and salary increase.