Table 2.

Design considerations for device prototype

Theme	Subtheme	Quotes/Examples
Accompaniments	Finger prick kit	“It would be cool if it came like in a little pouch where like your lancets can go in there and your little slides that you have to stick it- like so that everything could be kept together. That would be helpful.” (Josephine, Provider)
	Device instructions in a variety of formations (e.g., video, written)	“We all learn in different ways. So I think there should be options for all three of them. Some people are visual, some people have to be taught, some people like reading.” (Jamal, PLHIV)
Assay	Lower limits of detection	“Even though some studies used over 400 are currently [suppressed] over 200 we [at the clinic] would say you’re not, that’s not considered suppressed. That’s definitely a reason to talk to your doctor. I think between 200 and whatever the threshold for undetectable is that is chosen if it’s less than 30 or less than 20. I think that would still be a reason to talk to your doctor because there’s some, somethings going on that’s keeping that individual from having an undetectable VL.” (Brooke, Provider)
Physical device	Charging port for phone	“Would I be able to charge my phone while it is heating?” (Aja, PLHIV)
	Compatibility with different models/sizes of phones	“… lots of people have lots of different types of smartphones would it only be able to work with certain ones, and that that may limit some, some people’s ability to, to even access it because people have all different kinds of phones?” (Brooke, provider)
Privacy Protection	Password protection and biometric controls (e.g., fingerprint/facial recognition)	“I really like when they’re able to use that like biometric control.” (Barron, PLHIV)
	Discrete app name and icon	“I would also have the option to make the, like, icon, like on their home screen or whatever, something very nondescript, something that doesn’t point to it being an HIV tracking thing. And that will kind of be my other worry, is people sort of knowing what the icon looks like even if it is something nondescript. You know, that the name has nothing to do with HIV.” (Sarah, Provider)
	Control over how to store data and for how long (e.g., locally on device or in cloud)	“Some people might want to store you know, five years of data on their phone and show ‘look I’ve been undetectable for five years’ sort of thing. Some might not want that, so I think if there was an option, you know, where they could just check a box or you know, slide something on the screen that’s like keep records for a year, keep records for five years, store to the cloud, you know, keep the most recent 10 records. I think they should all be sent to the clinic and then we would have them in indefinitely. So I think that’s something that the patient should be able to decide” (Sarah, Provider)
Sharing Information with Medical Providers	Automatically share medical results with providers	“If there’s a way that that data could be, you could select to have it automatically sent to your provider… the auto information to your provider, I think would be an excellent feature.” (Barron, PLHIV)
	Include specifics of data as well as additional information (e.g., date of test, VL result, if they took their medication, how they are feeling, and a notes section)	“It would be really interesting if you could capture a couple of things… like whether or not they were ill at the times. So, if someone is sick with an upper respiratory infection, or gastroenteritis or something, their VL may get all out of whack… it would be really interesting to also get a sense of their adherence to their antiretroviral regimen in the time preceding any VL testing.” (Brooke, Provider)
	Frequency of data report to providers	“if it was someone who was needing, for some reason, needing to test very frequently, I wouldn’t want to wait a whole year before understanding where their VL was. If it was someone who’s just monitoring a couple of times a year, then maybe, they got to that point because they were more stable, and we wouldn’t need to see it as frequently.” (Brooke, Provider)
App Design	Simple interface	“I like to keep things really simple because when things are complicated for me, I shut down.” (Michelle, PLHIV)
	Value neutral colors for results	“But high VL isn’t wrong. So why is it red?… Red is cautionary right?” (Eli, PLHIV) “Wait. Wait, something’s wrong. Code Red, right.” (Eli, PLHIV)
	Language that is familiar to PLHIV (e.g., detectable/ undetectable instead of high/low VL)	“I would go with like the detectable/undetectable. That’s kind of what’s been conditioned into patients just because it’s the way our assays readout.” (Adam, Provider) “For me suppressed is a lot blurrier whereas detectable versus undetectable is fairly black and white. So, I prefer those terms.” (Barron, PLHIV)
	Numerical data	“I definitely wouldn’t use high and low and I wouldn’t use all clear either. I literally say you know, suppressed- um If it was suppressed or undetectable, I wouldn’t do anything besides like great. It’s green… and if it was detectable or unsuppressed I would say like, please contact your doctor, but I would have the number displayed. So… high VL like what does that mean? Is it 21 when our threshold is 20 or is it, you know, 200,000? That’s a big difference.” (Sarah, Provider)
	Reminder/trackers (e.g., medication, appointment, and/or symptoms)	“There’s still some clients who need to be reminded about taking pills right now, so a little bit of help with would be a good idea on that perspective.” (Jaime, PLHIV)
	View of data over time	“I think if the data were stored. Like, all results were stored in the app, like in a way that you could just like review them over time. That would be cool too, because then you could like, not only know your data points, but you could see any trends that might be occurring” (Barron, PLHIV). “I like being able to look at trends over time” (Adam, Provider)
	Progress indicator to indicate test completion or error	“I love that because I think we all need that feedback that something is actually working.” (Josephine, Provider) “It would be nice if like a could like sending an error message if something is not being done correctly. To remind to remind the person that oh, you, you forgot a step or something like that.” (Nolan, PLHIV)
	A menu of preferences to customize features and privacy settings	“Something that would be cool. Yeah, like when you log in and like, you know, add whatever demographics you want to, like, often would you like to test like, chime and be like, hey, you know? Test day or whatever. That’d be cool.” (Barron, PLHIV)
Additional information	HIV information and resources	“Just basic what is VL, what is a CD4 count…Just sort of basic education, what is u equals u?” (Sarah, Provider) “I think that having some sort of information on how to be a self-advocate or even have resources to help advocates would be valuable” (Eli, PLHIV)
	Inspirational messaging	“I think content about positive affirmations. Uh just reminders, calmness… so things like tricks on how to take medication. If you can’t swallow the pills or if you miss a dose, it’s okay, you know those types of things that you would normally get from a support group that can automatically be on the device would be great.” (Michelle, PLHIV) “I mean they could go so far as to put in little positive sayings. For you everyday to look at or go pick me ups.” (Donna, PLHIV)
	Tailored messaging	“Yeah. Yeah. Something cute and sweet on their birthday. Just to let em know you’re thinking of them and give them a reason to be happy that they made it through another year swallowing those great pills [sarcasm]” (Donna, PLHIV) “Like if your VL is undetectable, or you have a low VL or whatever it states that maybe you get like, some sort of affirmation, like you’re doing great or keep up the keep up the good work” (Eli, PLHIV) “If there is educational message messaging, that would be result dependent. So, if their VL was higher, it’s just reminding them like, ‘hey, you know, you’re more likely to transmit to someone else with this.’” (Adam, provider)

PLHIV = person living with HIV; VL = viral load.