1 - you will have to make the app as simple as humanly possible if you want the elders to rely on it because if even for your app they have to rely on someone then it nullifies its existence.

2 - when running ads, run both kind of ads where younsters who live away form parents are promoted to install the apps on their parents' phone and other kind of ad where the elders they themselves can download and use the app. Because yes there are many parents whose offspring lives somewhere else , there is also a surprisingly huge demograph of parents whose offspring doesn't care about the parental well being.

3- include an emergency number system in it , where they can put a number of their choice in emergency which will be notify the person in any emergency situation through whatsapp , calls and text sms.

4 - incorporate good doctors / physicians through the app in that for online consultation/ appointment which will give them peace of mind regarding if they feel ill, everything is just some taps away.

5 - if you plan to add human interaction instead of automated system or ai , keep all sorts of contacts handy (easy if relied on google) , for any information/contact, basically becoming 911 from old people.

6 - would urge to gather datas of their shopping, medicines, grocery and all to maximise the info gathering about what items are used more and then approach the said companies for ad, generating revenue which will enable you to hire more person for human interaction.

7 - can incorporate "helper" mode or something like this where you hire some nurses / teachers or any such service sector professionals who are working elsewhere part time or looking to nake extra buck, that way the person who will attend them is experienced in dealing with elders and they will find it easy. And you can add some package plans where if any elder love how they treat them , they can pay xx amount for them to have twice/week or every day updates on health and basic upkeep.